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The Trunk: Regex-Help-pre.1.mcz
by commits＠source.squeak.org 12 Oct '22

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Patrick Rein uploaded a new version of Regex-Help to project The Trunk: http://source.squeak.org/trunk/Regex-Help-pre.1.mcz ==================== Summary ==================== Name: Regex-Help-pre.1 Author: pre Time: 6 July 2018, 5:14:56.533269 pm UUID: 476b203d-1709-a54e-9a96-f0dfc3a93dfd Ancestors: Converts the regex documentation from class methods to a full help topic. ==================== Snapshot ==================== SystemOrganization addCategory: #'Regex-Help'! CustomHelp subclass: #RegexHelp instanceVariableNames: '' classVariableNames: '' poolDictionaries: '' category: 'Regex-Help'! ----- Method: RegexHelp class>>bookName (in category 'as yet unclassified') ----- bookName ^ 'Regex'! ----- Method: RegexHelp class>>changelog (in category 'as yet unclassified') ----- changelog "This method was automatically generated. Edit it using:" "RegexHelp edit: #changelog" ^(HelpTopic title: 'Changelog' contents: 'VERSION 1.3.1 (September 2008) 1. Updated documentation of character classes, making clear the problems of locale - an area for future improvement VERSION 1.3 (September 2008) 1. \w now matches underscore as well as alphanumerics, in line with most other regex libraries (and our documentation!!!!). 2. \W rejects underscore as well as alphanumerics 3. added tests for this at end of testSuite 4. updated documentation and added note to old incorrect comments in version 1.1 below VERSION 1.2.3 (November 2007) 1. Regexs with ^ or $ applied to copy empty strings caused infinite loops, e.g. ('''' copyWithRegex: ''^.*$'' matchesReplacedWith: ''foo''). Applied a similar correction to that from version 1.1c, to #copyStream:to:(replacingMatchesWith:|translatingMatchesUsing:). 2. Extended RxParser testing to run each test for #copy:translatingMatchesUsing: as well as #search:. 3. Corrected #testSuite test that a dot does not match a null, which was passing by luck with Smalltalk code in a literal array. 4. Added test to end of test suite for fix 1 above. VERSION 1.2.2 (November 2006) There was no way to specify a backslash in a character set. Now [\\] is accepted. VERSION 1.2.1 (August 2006) 1. Support for returning all ranges (startIndex to: stopIndex) matching a regex - #allRangesOfRegexMatches:, #matchingRangesIn: 2. Added hint to usage documentation on how to get more information about matches when enumerating 3. Syntax description of dot corrected: matches anything but NUL since 1.1a VERSION 1.2 (May 2006) Fixed case-insensitive search for character sets. VERSION 1.1c (December 2004) Fixed the issue with #matchesOnStream:do: which caused infinite loops for matches that matched empty strings. VERSION 1.1b (November 2001) Changes valueNowOrOnUnwindDo: to ensure:, plus incorporates some earlier fixes. VERSION 1.1a (May 2001) 1. Support for keeping track of multiple subexpressions. 2. Dot (.) matches anything but NUL character, as it should per POSIX spec. 3. Some bug fixes. VERSION 1.1 (October 1999) Regular expression syntax corrections and enhancements: 1. Backslash escapes similar to those in Perl are allowed in patterns: \w any word constituent character (equivalent to [a-zA-Z0-9_]) *** underscore only since 1.3 *** \W any character but a word constituent (equivalent to [^a-xA-Z0-9_] *** underscore only since 1.3 *** \d a digit (same as [0-9]) \D anything but a digit \s a whitespace character \S anything but a whitespace character \b an empty string at a word boundary \B an empty string not at a word boundary \< an empty string at the beginning of a word \> an empty string at the end of a word For example, ''\w+'' is now a valid expression matching any word. 2. The following backslash escapes are also allowed in character sets (between square brackets): \w, \W, \d, \D, \s, and \S. 3. The following grep(1)-compatible named character classes are recognized in character sets as well: [:alnum:] [:alpha:] [:cntrl:] [:digit:] [:graph:] [:lower:] [:print:] [:punct:] [:space:] [:upper:] [:xdigit:] For example, the following patterns are equivalent: ''[[:alnum:]_]+'' ''\w+'' ''[\w]+'' ''[a-zA-Z0-9_]+'' *** underscore only since 1.3 *** 4. Some non-printable characters can be represented in regular expressions using a common backslash notation: \t tab (Character tab) \n newline (Character lf) \r carriage return (Character cr) \f form feed (Character newPage) \e escape (Character esc) 5. A dot is corectly interpreted as ''any character but a newline'' instead of ''anything but whitespace''. 6. Case-insensitive matching. The easiest access to it are new messages CharacterArray understands: #asRegexIgnoringCase, #matchesRegexIgnoringCase:, #prefixMatchesRegexIgnoringCase:. 7. The matcher (an instance of RxMatcher, the result of String>>asRegex) now provides a collection-like interface to matches in a particular string or on a particular stream, as well as substitution protocol. The interface includes the following messages: matchesIn: aString matchesIn: aString collect: aBlock matchesIn: aString do: aBlock matchesOnStream: aStream matchesOnStream: aStream collect: aBlock matchesOnStream: aStream do: aBlock copy: aString translatingMatchesUsing: aBlock copy: aString replacingMatchesWith: replacementString copyStream: aStream to: writeStream translatingMatchesUsing: aBlock copyStream: aStream to: writeStream replacingMatchesWith: aString Examples: ''\w+'' asRegex matchesIn: ''now is the time'' returns an OrderedCollection containing four strings: ''now'', ''is'', ''the'', and ''time''. ''\<t\w+'' asRegexIgnoringCase copy: ''now is the Time'' translatingMatchesUsing: [:match | match asUppercase] returns ''now is THE TIME'' (the regular expression matches words beginning with either an uppercase or a lowercase T). ACKNOWLEDGEMENTS Since the first release of the matcher, thanks to the input from several fellow Smalltalkers, I became convinced a native Smalltalk regular expression matcher was worth the effort to keep it alive. For the contributions, suggestions, and bug reports that made this release possible, I want to thank: Felix Hack Peter Hatch Alan Knight Eliot Miranda Thomas Muhr Robb Shecter David N. Smith Francis Wolinski and anyone whom I haven''t yet met or heard from, but who agrees this has not been a complete waste of time.!!' readStream nextChunkText) key: #changelog! ----- Method: RegexHelp class>>examples (in category 'as yet unclassified') ----- examples "This method was automatically generated. Edit it using:" "RegexHelp edit: #examples" ^(HelpTopic title: 'Examples' contents: 'As the introductions said, a great use for regular expressions is userinput validation. Following are a few examples of regular expressionsthat might be handy in checking input entered by the user in an inputfield. Try them out by entering something between the quotes andprint-iting. (Also, try to imagine Smalltalk code that each validationwould require if coded by hand). Most example expressions could havebeen written in alternative ways. Checking if aString may represent a nonnegative integer number: '''' matchesRegex: '':isDigit:+''or '''' matchesRegex: ''[0-9]+''or '''' matchesRegex: ''\d+'' Checking if aString may represent an integer number with an optionalsign in front: '''' matchesRegex: ''(\+|-)?\d+'' Checking if aString is a fixed-point number, with at least one digitis required after a dot: '''' matchesRegex: ''(\+|-)?\d+(\.\d+)?'' The same, but allow notation like `123.'': '''' matchesRegex: ''(\+|-)?\d+(\.\d*)?'' Recognizer for a string that might be a name: one word with firstcapital letter, no blanks, no digits. More traditional: '''' matchesRegex: ''[A-Z][A-Za-z]*'' more Smalltalkish: '''' matchesRegex: '':isUppercase::isAlphabetic:*'' A date in format MMM DD, YYYY with any number of spaces in between, inXX century: '''' matchesRegex: ''(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[ ]+(\d\d?)[ ]*,[ ]*19(\d\d)'' Note parentheses around some components of the expression above. As`Usage'' section shows, they will allow us to obtain the actual stringsthat have matched them (i.e. month name, day number, and year number). For dessert, coming back to numbers: here is a recognizer for ageneral number format: anything like 999, or 999.999, or -999.999e+21. '''' matchesRegex: ''(\+|-)?\d+(\.\d*)?((e|E)(\+|-)?\d+)?''!!!!!!' readStream nextChunkText) key: #examples! ----- Method: RegexHelp class>>implementationNotes (in category 'as yet unclassified') ----- implementationNotes "This method was automatically generated. Edit it using:" "RegexHelp edit: #implementationNotes" ^(HelpTopic title: 'Implementation Notes' contents: 'WHAT TO LOOK AT FIRST String>>matchesRegex: -- in 90% cases this method is all you need to access the package. RxParser -- accepts a string or a stream of characters with a regular expression, and produces a syntax tree corresponding to the expression. The tree is made of instances of Rxs<whatever> classes. RxMatcher -- accepts a syntax tree of a regular expression built by the parser and compiles it into a matcher: a structure made of instances of Rxm<whatever> classes. The RxMatcher instance can test whether a string or a positionable stream of characters matches the original regular expression, or search a string or a stream for substrings matching the expression. After a match is found, the matcher can report a specific string that matched the whole expression, or any parenthesized subexpression of it. All other classes support the above functionality and are used by RxParser, RxMatcher, or both. CAVEATS The matcher is similar in spirit, but NOT in the design--let alone the code--to the original Henry Spencer''s regular expression implementation in C. The focus is on simplicity, not on efficiency. I didn''t optimize or profile anything. I may in future--or I may not: I do this in my spare time and I don''t promise anything. The matcher passes H. Spencer''s test suite (see ''test suite'' protocol), with quite a few extra tests added, so chances are good there are not too many bugs. But watch out anyway. EXTENSIONS, FUTURE, ETC. With the existing separation between the parser, the syntax tree, and the matcher, it is easy to extend the system with other matchers based on other algorithms. In fact, I have a DFA-based matcher right now, but I don''t feel it is good enough to include it here. I might add automata-based matchers later, but again I don''t promise anything. HOW TO REACH ME As of today (December 20, 2000), you can contact me at <vassili(a)parcplace.com>. If this doesn''t work, look around comp.lang.smalltalk or comp.lang.lisp. !!' readStream nextChunkText) key: #implementationNotes! ----- Method: RegexHelp class>>introduction (in category 'as yet unclassified') ----- introduction "This method was automatically generated. Edit it using:" "RegexHelp edit: #introduction" ^(HelpTopic title: 'Introduction' contents: 'A regular expression is a template specifying a class of strings. A regular expression matcher is an tool that determines whether a string belongs to a class specified by a regular expression. This is a common task of a user input validation code, and the use of regular expressions can GREATLY simplify and speed up development of such code. As an example, here is how to verify that a string is a valid hexadecimal number in Smalltalk notation, using this matcher package: aString matchesRegex: ''16r[[:xdigit:]]+'' (Coding the same "the hard way'''' is an exercise to a curious reader). This matcher is offered to the Smalltalk community in hope it will be useful. It is free in terms of money, and to a large extent -- in terms of rights of use. Refer to the "Boring Stuff" section for legalese. The "Syntax" section explains the recognized syntax of regular expressions. The "Usage" section explains matcher capabilities that go beyond what String>>matchesRegex: method offers. The "Implementation Notes" sections says a few words about what is under the hood. The "Changelog" section describes the functionality introduced in 1.1 release. Happy hacking, --Vassili Bykov <vassili(a)objectpeople.com> <vassili(a)magma.ca> !! ]style[(479 40 712),daString matchesRegex: ''16r[[:xdigit:]]+'';;,!!' readStream nextChunkText) key: #introduction! ----- Method: RegexHelp class>>license (in category 'as yet unclassified') ----- license "This method was automatically generated. Edit it using:" "RegexHelp edit: #license" ^(HelpTopic title: 'License' contents: 'The Regular Expression Matcher (``The Software'''') is Copyright (C) 1996, 1999 Vassili Bykov. It is provided to the Smalltalk community in hope it will be useful. 1. This license applies to the package as a whole, as well as to any component of it. By performing any of the activities described below, you accept the terms of this agreement. 2. The software is provided free of charge, and "as is'''', in hope that it will be useful, with ABSOLUTELY NO WARRANTY. The entire risk and all responsibility for the use of the software is with you. Under no circumstances the author may be held responsible for loss of data, loss of profit, or any other damage resulting directly or indirectly from the use of the software, even if the damage is caused by defects in the software. 3. You may use this software in any applications you build. 4. You may distribute this software provided that the software documentation and copyright notices are included and intact. 5. You may create and distribute modified versions of the software, such as ports to other Smalltalk dialects or derived work, provided that: a. any modified version is expressly marked as such and is not misrepresented as the original software; b. credit is given to the original software in the source code and documentation of the derived work; c. the copyright notice at the top of this document accompanies copyright notices of any modified version.!!' readStream nextChunkText) key: #license! ----- Method: RegexHelp class>>pages (in category 'as yet unclassified') ----- pages ^ #(introduction syntax examples usage implementationNotes license changelog)! ----- Method: RegexHelp class>>syntax (in category 'as yet unclassified') ----- syntax "This method was automatically generated. Edit it using:" "RegexHelp edit: #syntax" ^(HelpTopic title: 'Syntax' contents: 'The simplest regular expression is a single character. It matchesexactly that character. A sequence of characters matches a string withexactly the same sequence of characters: ''a'' matchesRegex: ''a'' -- true ''foobar'' matchesRegex: ''foobar'' -- true ''blorple'' matchesRegex: ''foobar'' -- false The above paragraph introduced a primitive regular expression (acharacter), and an operator (sequencing). Operators are applied toregular expressions to produce more complex regular expressions.Sequencing (placing expressions one after another) as an operator is,in a certain sense, ''invisible''--yet it is arguably the most common. A more ''visible'' operator is Kleene closure, more often simplyreferred to as ''a star''. A regular expression followed by an asteriskmatches any number (including 0) of matches of the originalexpression. For example: ''ab'' matchesRegex: ''a*b'' -- true ''aaaaab'' matchesRegex: ''a*b'' -- true ''b'' matchesRegex: ''a*b'' -- true ''aac'' matchesRegex: ''a*b'' -- false: b does not match A star''s precedence is higher than that of sequencing. A star appliesto the shortest possible subexpression that precedes it. For example,''ab*'' means ''a followed by zero or more occurrences of b'', not ''zeroor more occurrences of ab'': ''abbb'' matchesRegex: ''ab*'' -- true ''abab'' matchesRegex: ''ab*'' -- false To actually make a regex matching ''zero or more occurrences of ab'',''ab'' is enclosed in parentheses: ''abab'' matchesRegex: ''(ab)*'' -- true ''abcab'' matchesRegex: ''(ab)*'' -- false: c spoils the fun Two other operators similar to ''*'' are ''+'' and ''?''. ''+'' (positiveclosure, or simply ''plus'') matches one or more occurrences of theoriginal expression. ''?'' (''optional'') matches zero or one, but nevermore, occurrences. ''ac'' matchesRegex: ''ab*c'' -- true ''ac'' matchesRegex: ''ab+c'' -- false: need at least one b ''abbc'' matchesRegex: ''ab+c'' -- true ''abbc'' matchesRegex: ''ab?c'' -- false: too many b''s As we have seen, characters ''*'', ''+'', ''?'', ''('', and '')'' have specialmeaning in regular expressions. If one of them is to be usedliterally, it should be quoted: preceded with a backslash. (Thus,backslash is also special character, and needs to be quoted for aliteral match--as well as any other special character describedfurther). ''ab*'' matchesRegex: ''ab*'' -- false: star in the right string is special ''ab*'' matchesRegex: ''ab\*'' -- true ''a\c'' matchesRegex: ''a\\c'' -- true The last operator is ''|'' meaning ''or''. It is placed between tworegular expressions, and the resulting expression matches if one ofthe expressions matches. It has the lowest possible precedence (lowerthan sequencing). For example, ''ab*|ba*'' means ''a followed by anynumber of b''s, or b followed by any number of a''s'': ''abb'' matchesRegex: ''ab*|ba*'' -- true ''baa'' matchesRegex: ''ab*|ba*'' -- true ''baab'' matchesRegex: ''ab*|ba*'' -- false A bit more complex example is the following expression, matching thename of any of the Lisp-style ''car'', ''cdr'', ''caar'', ''cadr'',... functions: c(a|d)+r It is possible to write an expression matching an empty string, forexample: ''a|''. However, it is an error to apply ''*'', ''+'', or ''?'' tosuch expression: ''(a|)*'' is an invalid expression. So far, we have used only characters as the ''smallest'' components ofregular expressions. There are other, more ''interesting'', components. A character set is a string of characters enclosed in squarebrackets. It matches any single character if it appears between thebrackets. For example, ''[01]'' matches either ''0'' or ''1'': ''0'' matchesRegex: ''[01]'' -- true ''3'' matchesRegex: ''[01]'' -- false ''11'' matchesRegex: ''[01]'' -- false: a set matches only one character Using plus operator, we can build the following binary numberrecognizer: ''10010100'' matchesRegex: ''[01]+'' -- true ''10001210'' matchesRegex: ''[01]+'' -- false If the first character after the opening bracket is ''^'', the set isinverted: it matches any single character *not* appearing between thebrackets: ''0'' matchesRegex: ''[^01]'' -- false ''3'' matchesRegex: ''[^01]'' -- true For convenience, a set may include ranges: pairs of charactersseparated with ''-''. This is equivalent to listing all charactersbetween them: ''[0-9]'' is the same as ''[0123456789]''. Special characters within a set are ''^'', ''-'', and '']'' that closes theset. Below are the examples of how to literally use them in a set: [01^] -- put the caret anywhere except the beginning [01-] -- put the dash as the last character []01] -- put the closing bracket as the first character [^]01] (thus, empty and universal sets cannot be specified) Regular expressions can also include the following backquote escapesto refer to popular classes of characters: \w any word constituent character (same as [a-zA-Z0-9_]) \W any character but a word constituent \d a digit (same as [0-9]) \D anything but a digit \s a whitespace character (same as [:space:] below) \S anything but a whitespace character These escapes are also allowed in character classes: ''[\w+-]'' means''any character that is either a word constituent, or a plus, or aminus''. Character classes can also include the following grep(1)-compatibleelements to refer to: [:alnum:] any alphanumeric character (same as [a-zA-Z0-9]) [:alpha:] any alphabetic character (same as [a-zA-Z]) [:cntrl:] any control character. (any character with code < 32) [:digit:] any decimal digit (same as [0-9]) [:graph:] any graphical character. (any character with code >= 32). [:lower:] any lowercase character (including non-ASCII lowercase characters) [:print:] any printable character. In this version, this is the same as [:graph:] [:punct:] any punctuation character: . , !!!!!!!! ? ; : '' - ( ) '' and double quotes [:space:] any whitespace character (space, tab, CR, LF, null, form feed, Ctrl-Z, 16r2000-16r200B, 16r3000) [:upper:] any uppercase character (including non-ASCII uppercase characters) [:xdigit:] any hexadecimal character (same as [a-fA-F0-9]). Note that many of these are only as consistent or inconsistent on issuesof locale as the underlying Smalltalk implementation. Values shown hereare for VisualWorks 7.6. Note that these elements are components of the character classes,i.e. they have to be enclosed in an extra set of square brackets toform a valid regular expression. For example, a non-empty string ofdigits would be represented as ''[[:digit:]]+''. The above primitive expressions and operators are common to manyimplementations of regular expressions. The next primitive expressionis unique to this Smalltalk implementation. A sequence of characters between colons is treated as a unary selectorwhich is supposed to be understood by Characters. A character matchessuch an expression if it answers true to a message with thatselector. This allows a more readable and efficient way of specifyingcharacter classes. For example, ''[0-9]'' is equivalent to '':isDigit:'',but the latter is more efficient. Analogously to character sets,character classes can be negated: '':^isDigit:'' matches a Characterthat answers false to #isDigit, and is therefore equivalent to''[^0-9]''. As an example, so far we have seen the following equivalent ways towrite a regular expression that matches a non-empty string of digits: ''[0-9]+'' ''\d+'' ''[\d]+'' ''[[:digit:]]+'' '':isDigit:+'' The last group of special primitive expressions includes: . matching any character except a NULL; ^ matching an empty string at the beginning of a line; $ matching an empty string at the end of a line. \b an empty string at a word boundary \B an empty string not at a word boundary \< an empty string at the beginning of a word \> an empty string at the end of a word ''axyzb'' matchesRegex: ''a.+b'' -- true ''ax zb'' matchesRegex: ''a.+b'' -- true (space is matched by ''.'') ''axzb'' matchesRegex: ''a.+b'' -- true (carriage return is matched by ''.'') Again, the dot ., caret ^ and dollar $ characters are special and should be quotedto be matched literally.!! ]style[(179 21 7851),f5,!!' readStream nextChunkText) key: #syntax! ----- Method: RegexHelp class>>usage (in category 'as yet unclassified') ----- usage "This method was automatically generated. Edit it using:" "RegexHelp edit: #usage" ^(HelpTopic title: 'Usage' contents: 'The preceding section covered the syntax of regular expressions. It used the simplest possible interface to the matcher: sending #matchesRegex: message to the sample string, with regular expression string as the argument. This section explains hairier ways of using the matcher. PREFIX MATCHING AND CASE-INSENSITIVE MATCHING A CharacterArray (an EsString in VA) also understands these messages: #prefixMatchesRegex: regexString #matchesRegexIgnoringCase: regexString #prefixMatchesRegexIgnoringCase: regexString #prefixMatchesRegex: is just like #matchesRegex, except that the whole receiver is not expected to match the regular expression passed as the argument; matching just a prefix of it is enough. For example: ''abcde'' matchesRegex: ''(a|b)+'' -- false ''abcde'' prefixMatchesRegex: ''(a|b)+'' -- true The last two messages are case-insensitive versions of matching. ENUMERATION INTERFACE An application can be interested in all matches of a certain regular expression within a String. The matches are accessible using a protocol modelled after the familiar Collection-like enumeration protocol: #regex: regexString matchesDo: aBlock Evaluates a one-argument <aBlock> for every match of the regular expression within the receiver string. #regex: regexString matchesCollect: aBlock Evaluates a one-argument <aBlock> for every match of the regular expression within the receiver string. Collects results of evaluations and anwers them as a SequenceableCollection. #allRegexMatches: regexString Returns a collection of all matches (substrings of the receiver string) of the regular expression. It is an equivalent of <aString regex: regexString matchesCollect: [:each | each]>. #allRangesOfRegexMatches: regexString Returns a collection of all character ranges (startIndex to: stopIndex) that match the regular expression. REPLACEMENT AND TRANSLATION It is possible to replace all matches of a regular expression with a certain string using the message: #copyWithRegex: regexString matchesReplacedWith: aString For example: ''ab cd ab'' copyWithRegex: ''(a|b)+'' matchesReplacedWith: ''foo'' A more general substitution is match translation: #copyWithRegex: regexString matchesTranslatedUsing: aBlock This message evaluates a block passing it each match of the regular expression in the receiver string and answers a copy of the receiver with the block results spliced into it in place of the respective matches. For example: ''ab cd ab'' copyWithRegex: ''(a|b)+'' matchesTranslatedUsing: [:each | each asUppercase] All messages of enumeration and replacement protocols perform a case-sensitive match. Case-insensitive versions are not provided as part of a CharacterArray protocol. Instead, they are accessible using the lower-level matching interface. LOWER-LEVEL INTERFACE Internally, #matchesRegex: works as follows: 1. A fresh instance of RxParser is created, and the regular expression string is passed to it, yielding the expression''s syntax tree. 2. The syntax tree is passed as an initialization parameter to an instance of RxMatcher. The instance sets up some data structure that will work as a recognizer for the regular expression described by the tree. 3. The original string is passed to the matcher, and the matcher checks for a match. THE MATCHER If you repeatedly match a number of strings against the same regular expression using one of the messages defined in CharacterArray, the regular expression string is parsed and a matcher is created anew for every match. You can avoid this overhead by building a matcher for the regular expression, and then reusing the matcher over and over again. You can, for example, create a matcher at a class or instance initialization stage, and store it in a variable for future use. You can create a matcher using one of the following methods: - Sending #forString:ignoreCase: message to RxMatcher class, with the regular expression string and a Boolean indicating whether case is ignored as arguments. - Sending #forString: message. It is equivalent to <... forString: regexString ignoreCase: false>. A more convenient way is using one of the two matcher-created messages understood by CharacterArray. - <regexString asRegex> is equivalent to <RxMatcher forString: regexString>. - <regexString asRegexIgnoringCase> is equivalent to <RxMatcher forString: regexString ignoreCase: true>. Here are four examples of creating a matcher: hexRecognizer := RxMatcher forString: ''16r[0-9A-Fa-f]+'' hexRecognizer := RxMatcher forString: ''16r[0-9A-Fa-f]+'' ignoreCase: false hexRecognizer := ''16r[0-9A-Fa-f]+'' asRegex hexRecognizer := ''16r[0-9A-F]+'' asRegexIgnoringCase MATCHING The matcher understands these messages (all of them return true to indicate successful match or search, and false otherwise): matches: aString True if the whole target string (aString) matches. matchesPrefix: aString True if some prefix of the string (not necessarily the whole string) matches. search: aString Search the string for the first occurrence of a matching substring. (Note that the first two methods only try matching from the very beginning of the string). Using the above example with a matcher for `a+'', this method would answer success given a string `baaa'', while the previous two would fail. matchesStream: aStream matchesStreamPrefix: aStream searchStream: aStream Respective analogs of the first three methods, taking input from a stream instead of a string. The stream must be positionable and peekable. All these methods answer a boolean indicating success. The matcher also stores the outcome of the last match attempt and can report it: lastResult Answers a Boolean -- the outcome of the most recent match attempt. If no matches were attempted, the answer is unspecified. SUBEXPRESSION MATCHES After a successful match attempt, you can query the specifics of which part of the original string has matched which part of the whole expression. A subexpression is a parenthesized part of a regular expression, or the whole expression. When a regular expression is compiled, its subexpressions are assigned indices starting from 1, depth-first, left-to-right. For example, `((ab)+(c|d))?ef'' includes the following subexpressions with these indices: 1: ((ab)+(c|d))?ef 2: (ab)+(c|d) 3: ab 4: c|d After a successful match, the matcher can report what part of the original string matched what subexpression. It understandards these messages: subexpressionCount Answers the total number of subexpressions: the highest value that can be used as a subexpression index with this matcher. This value is available immediately after initialization and never changes. subexpression: anIndex An index must be a valid subexpression index, and this message must be sent only after a successful match attempt. The method answers a substring of the original string the corresponding subexpression has matched to. subBeginning: anIndex subEnd: anIndex Answer positions within the original string or stream where the match of a subexpression with the given index has started and ended, respectively. This facility provides a convenient way of extracting parts of input strings of complex format. For example, the following piece of code uses the ''MMM DD, YYYY'' date format recognizer example from the `Syntax'' section to convert a date to a three-element array with year, month, and day strings (you can select and evaluate it right here): | matcher | matcher := RxMatcher forString: ''(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[ ]+(:isDigit::isDigit:?)[ ]*,[ ]*(19|20)(:isDigit::isDigit:)''. (matcher matches: ''Aug 6, 1996'') ifTrue: [Array with: (matcher subexpression: 5) with: (matcher subexpression: 2) with: (matcher subexpression: 3)] ifFalse: [''no match''] (should answer ` #(''96'' ''Aug'' ''6'')''). ENUMERATION AND REPLACEMENT The enumeration and replacement protocols exposed in CharacterArray are actually implemented by the matcher. The following messages are understood: #matchesIn: aString #matchesIn: aString do: aBlock #matchesIn: aString collect: aBlock #copy: aString replacingMatchesWith: replacementString #copy: aString translatingMatchesUsing: aBlock #matchingRangesIn: aString #matchesOnStream: aStream #matchesOnStream: aStream do: aBlock #matchesOnStream: aStream collect: aBlock #copy: sourceStream to: targetStream replacingMatchesWith: replacementString #copy: sourceStream to: targetStream translatingMatchesWith: aBlock Note that in those methods that take a block, the block may refer to the rxMatcher itself, e.g. to collect information about the position the match occurred at, or the subexpressions of the match. An example can be seen in #matchingRangesIn: ERROR HANDLING Exception signaling objects (Signals in VisualWorks, Exceptions in VisualAge) are accessible through RxParser class protocol. To handle possible errors, use the protocol described below to obtain the exception objects and use the protocol of the native Smalltalk implementation to handle them. If a syntax error is detected while parsing expression, RxParser>>syntaxErrorSignal is raised/signaled. If an error is detected while building a matcher, RxParser>>compilationErrorSignal is raised/signaled. If an error is detected while matching (for example, if a bad selector was specified using `:<selector>:'' syntax, or because of the matcher''s internal error), RxParser>>matchErrorSignal is raised RxParser>>regexErrorSignal is the parent of all three. Since any of the three signals can be raised within a call to #matchesRegex:, it is handy if you want to catch them all. For example: VisualWorks: RxParser regexErrorSignal handle: [:ex | ex returnWith: nil] do: [''abc'' matchesRegex: ''))garbage[''] VisualAge: [''abc'' matchesRegex: ''))garbage[''] when: RxParser regexErrorSignal do: [:signal | signal exitWith: nil]!!' readStream nextChunkText) key: #usage!

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by commits＠source.squeak.org 09 Sep '22

09 Sep '22

A new version of Kernel was added to project The Inbox: http://source.squeak.org/inbox/Kernel-ct.1294.mcz ==================== Summary ==================== Name: Kernel-ct.1294 Author: ct Time: 9 January 2020, 3:42:36.672555 pm UUID: 7409dcc3-160e-9d44-9712-f266e0f25973 Ancestors: Kernel-nice.1292 Proposal: Add #haltOnceIf: to Object, which combines the strengths of #haltOnce and #haltIf:. Especially useful in performance-critical situations: It HaltOnce is disabled, the condition will not be evaluated at all. =============== Diff against Kernel-nice.1292 =============== Item was changed: ----- Method: Object>>haltIf: (in category 'debugging') ----- + haltIf: aCondition + "This is the typical message to use for inserting breakpoints during debugging. Param can be a block or expression, halt if true. - haltIf: condition - "This is the typical message to use for inserting breakpoints during - debugging. Param can be a block or expression, halt if true. If the Block has one arg, the receiver is bound to that. + If the condition is a selector, we look up in the callchain. Halt if any method's selector equals selector." - If the condition is a selector, we look up in the callchain. Halt if - any method's selector equals selector." - | cntxt | + ^ (self meetsHaltCondition: aCondition) + ifTrue: [self halt]! - condition isSymbol ifTrue:[ - "only halt if a method with selector symbol is in callchain" - cntxt := thisContext. - [cntxt sender isNil] whileFalse: [ - cntxt := cntxt sender. - (cntxt selector = condition) ifTrue: [Halt signal]. - ]. - ^self. - ]. - (condition isBlock - ifTrue: [condition cull: self] - ifFalse: [condition] - ) ifTrue: [ - Halt signal - ].! Item was added: + ----- Method: Object>>haltOnceIf: (in category 'debugging') ----- + haltOnceIf: aCondition + "Check aCondition and halt, unless we have already done it once. See #meetsHaltCondition:." + + self haltOnceEnabled ifFalse: [^ self]. + ^ (self meetsHaltCondition: aCondition) + ifTrue: [ + self clearHaltOnce; halt].! Item was added: + ----- Method: Object>>meetsHaltCondition: (in category 'debugging') ----- + meetsHaltCondition: aCondition + "If the Block has one arg, the receiver is bound to that. + If the condition is a selector, we look up in the callchain. Halt if any method's selector equals selector." + + aCondition isSymbol ifTrue: [ | ctxt | + "only halt if a method with selector symbol is in callchain" + ctxt := thisContext. + [(ctxt := ctxt sender) isNil] whileFalse: [ + (ctxt selector = aCondition) ifTrue: [^ true] ]. + ^ false ]. + ^ aCondition isBlock + ifTrue: [aCondition cull: self] + ifFalse: [aCondition value]!

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SequenceableCollection #= method in current trunk differs from Squeak 5.2
by Nikolay Suslov 07 Jul '22

07 Jul '22

Hello all, Figuring out, could we go back to the previous version of SequenceableCollection #= method (as in Squeak 5.2), to check if the receiver is equivalent to the otherCollection by using "self species == otherCollection species", instead of "self class = otherCollection class"? The current version of #= method breaks code in different places. For example the RFB/VNC server gives wrong results starting from an authentication process, where RFBMessage is the ByteArray subclass and implements #species. Best regards, Nikolai

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Unicode
by Thiede, Christoph 15 Jun '22

15 Jun '22

Hi all! :-) After some recent fun with the Unicode class, I found out that its data is quite out of date (for example, the comments do not even "know" that code points can be longer than 4 bytes. Younger characters such as 😺❤🤓 are not categorized correctly, etc. ...). Luckily, there is already some logic to fetch the latest data from www.unicode.org<http://www.unicode.org>. I'm currently reworking this logic because it's not completely automated yet and has some slips, but so long, I have one general question for you: At the moment, we have 30 class variables each for one Unicode category number. These class vars map in alphabetical order to the integers from 0 to: 29. Is this tedious structure really necessary? For different purposes, I would like to get the category name of a specific code point from a client. The current design makes this impossible without writing additional mappings. Tl;dr: I would like to propose to drop these class variables and use Symbols instead. They are comparable like integers, and as they are flyweights, this should not be a performance issue either. Of course, #generalCategoryOf: will have to keep returning numbers, but we could deprecate it and use a new #generalTagOf: in the future. Furthermore, this would also allow us to deal with later added category names (though I don't know whether this will ever happen). Examples: Unicode generalTagOf: $a asUnicode. "#Ll" Unicode class >> isLetterCode: charCode ^ (self generalTagOf: charCode) first = $L Unicode class >> isAlphaNumericCode: charCode | tag| ^ (tag := self generalCategoryOf: charCode) first = $L or: [tag = #Nd] How do you think about this proposal? Please let me know and I will go ahead! :D Best, Christoph

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The Inbox: Collections-ct.877.mcz
by commits＠source.squeak.org 04 May '22

04 May '22

Christoph Thiede uploaded a new version of Collections to project The Inbox: http://source.squeak.org/inbox/Collections-ct.877.mcz ==================== Summary ==================== Name: Collections-ct.877 Author: ct Time: 17 February 2020, 8:57:49.278239 pm UUID: bf652ba0-43cc-734d-ac03-7a226cc80463 Ancestors: Collections-ul.875 Extends and realigns version of #findFirst: and #findLast:. Second, optimized version after many helpful comments by Levente (ul). Thank you! Replaces Collections-ct.875. --- Performance analysis: #findFirst: - '238 per second. 4.2 milliseconds per run. 0.73956 % GC time.' #findFirst:startingAt: - '1,510 per second. 660 microseconds per run. 1.56 % GC time.' #findFirst:startingAt:ifNone: - '1,210 per second. 828 microseconds per run. 2.06 % GC time.' #findFirst:ifNone: - '214 per second. 4.68 milliseconds per run. 0.65987 % GC time.' #findLast: - '210 per second. 4.76 milliseconds per run. 0.66 % GC time.' #findLast:startingAt: - '1,380 per second. 724 microseconds per run. 1.72 % GC time.' #findLast:startingAt:ifNone: - '1,130 per second. 887 microseconds per run. 2 % GC time.' #findLast:ifNone: - '206 per second. 4.86 milliseconds per run. 0.81967 % GC time.' Comparing to previous version: #findFirst: - '193 per second. 5.19 milliseconds per run. 0.5994 % GC time.' (NOW 23.3% faster) #findLast: - '213 per second. 4.69 milliseconds per run. 0.71986 % GC time.' (NOW 1.4% slower) #findLast:startingAt: - '1,360 per second. 736 microseconds per run. 1.72 % GC time.' (NOW 1.4% faster) Measurements code: random := Random new. range := 1 to: 256. array := (1 to: 128) collect: [:i | range atRandom: random]. values := (1 to: 4096) collect: [:i | range atRandom: random]. ({ #findFirst: -> [ values do: [:x | array findFirst: [:y | x = y]]]. #findFirst:startingAt: -> [ values pairsDo: [:x :s | array findFirst: [:y | x = y] startingAt: s]]. #findFirst:ifNone: -> [ values do: [:x | array findFirst: [:y | x = y] ifNone: [123456789 sqrt]]]. #findFirst:startingAt:ifNone: -> [ values pairsDo: [:x :s | array findFirst: [:y | x = y] startingAt: s ifNone: [123456789 sqrt]]]. #findLast: -> [ values do: [:x | array findLast: [:y | x = y]]]. #findLast:startingAt: -> [ values pairsDo: [:x :s | array findLast: [:y | x = y] startingAt: s]]. #findLast:ifNone: -> [ values do: [:x | array findLast: [:y | x = y] ifNone: [123456789 sqrt]]]. #findLast:startingAt:ifNone: -> [ values pairsDo: [:x :s | array findLast: [:y | x = y] startingAt: s ifNone: [123456789 sqrt]]]. } select: [:assoc | array respondsTo: assoc key]) collect: [:assoc | assoc key -> assoc value bench] as: Dictionary =============== Diff against Collections-ul.875 =============== Item was changed: ----- Method: SequenceableCollection>>findFirst: (in category 'enumerating') ----- findFirst: aBlock "Return the index of my first element for which aBlock evaluates as true." + ^ self findFirst: aBlock startingAt: 1! - | index | - index := 0. - [(index := index + 1) <= self size] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. - ^ 0! Item was added: + ----- Method: SequenceableCollection>>findFirst:ifNone: (in category 'enumerating') ----- + findFirst: aBlock ifNone: anotherBlock + "Return the index of my first element for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + (index := self findFirst: aBlock) = 0 + ifTrue: [^ anotherBlock value]. + ^ index! Item was added: + ----- Method: SequenceableCollection>>findFirst:startingAt: (in category 'enumerating') ----- + findFirst: aBlock startingAt: minIndex + "Return the index of my first element with index >= minIndex for which aBlock evaluates as true." + + minIndex to: self size do: [:index | + (aBlock value: (self at: index)) ifTrue: [^index]]. + ^ 0! Item was added: + ----- Method: SequenceableCollection>>findFirst:startingAt:ifNone: (in category 'enumerating') ----- + findFirst: aBlock startingAt: minIndex ifNone: anotherBlock + "Return the index of my first element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + (index := self findFirst: aBlock startingAt: minIndex) = 0 + ifTrue: [^ anotherBlock value]. + ^ index! Item was changed: ----- Method: SequenceableCollection>>findLast: (in category 'enumerating') ----- findLast: aBlock "Return the index of my last element for which aBlock evaluates as true." + ^ self findLast: aBlock startingAt: 1! - | index | - index := self size + 1. - [(index := index - 1) >= 1] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. - ^ 0! Item was added: + ----- Method: SequenceableCollection>>findLast:ifNone: (in category 'enumerating') ----- + findLast: aBlock ifNone: anotherBlock + "Return the index of my last element for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + (index := self findLast: aBlock) = 0 + ifTrue: [^ anotherBlock value]. + ^ index! Item was changed: ----- Method: SequenceableCollection>>findLast:startingAt: (in category 'enumerating') ----- + findLast: aBlock startingAt: minIndex + "Return the index of my last element with index >= minIndex for which aBlock evaluates as true." - findLast: aBlock startingAt: i - "Return the index of my last element with index >= i for which aBlock evaluates as true." + self size to: minIndex by: -1 do: [:index | + (aBlock value: (self at: index)) ifTrue: [^index]]. - | index | - index := self size + 1. - [(index := index - 1) >= i] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. ^ 0! Item was added: + ----- Method: SequenceableCollection>>findLast:startingAt:ifNone: (in category 'enumerating') ----- + findLast: aBlock startingAt: minIndex ifNone: anotherBlock + "Return the index of my last element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + (index := self findLast: aBlock startingAt: minIndex) = 0 + ifTrue: [^ anotherBlock value]. + ^ index!

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PositionableStream >> #peekBack behavior
by Eric Gade 04 May '22

04 May '22

Hello, What is the expected behavior for a stream that is at position 1 when you send #peekBack? Intuitively I'd expect to get the first element of the underlying collection as a response. But instead I am getting nil. Here is an example that is failing: ``` elem := #(1 2 3 4). stream := ReadStream on: elem. first := stream next. first = 1. back := stream peekBack. back = first. ``` The last message is currently responding false. In Pharo this returns true, so there are differences. The currently implementation of PositionableStream >> #peekBack is: ``` peekBack "Return the element at the previous position, without changing position. Use indirect messages in case self is a StandardFileStream." | element | self position = 0 ifTrue: [self errorCantGoBack]. self position = 1 ifTrue: [self position: 0. ^ nil]. self skip: -2. element := self next. self skip: 1. ^ element ``` I can see the nil being returned there explicitly, so that's "where it's happening." Should this be the case though? Thanks -- Eric

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The Inbox: Collections-ct.860.mcz
by commits＠source.squeak.org 07 Apr '22

07 Apr '22

A new version of Collections was added to project The Inbox: http://source.squeak.org/inbox/Collections-ct.860.mcz ==================== Summary ==================== Name: Collections-ct.860 Author: ct Time: 15 November 2019, 1:58:56.418005 pm UUID: f6364e7f-08c8-694a-9060-21bc0a0c28d4 Ancestors: Collections-pre.857 Add convenience constructor for Dictionary Dictionary fromKeys: 'wasd' values: '8426' =============== Diff against Collections-pre.857 =============== Item was added: + ----- Method: Dictionary class>>fromKeys:values: (in category 'instance creation') ----- + fromKeys: keys values: values + + | dictionary | + self assert: [keys size = values size]. + dictionary := self new: keys size. + keys with: values do: [:key :value | + dictionary add: key -> value]. + ^ dictionary!

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The Inbox: Collections-ct.875.mcz
by commits＠source.squeak.org 07 Apr '22

07 Apr '22

A new version of Collections was added to project The Inbox: http://source.squeak.org/inbox/Collections-ct.875.mcz ==================== Summary ==================== Name: Collections-ct.875 Author: ct Time: 16 February 2020, 3:32:23.116 pm UUID: 61ea773b-1408-c040-a712-09238ee6fe2f Ancestors: Collections-topa.873 Extends and realigns version of #findFirst: and #findLast:. =============== Diff against Collections-topa.873 =============== Item was changed: ----- Method: SequenceableCollection>>findFirst: (in category 'enumerating') ----- findFirst: aBlock - "Return the index of my first element for which aBlock evaluates as true." + ^ self findFirst: aBlock startingAt: 1! - | index | - index := 0. - [(index := index + 1) <= self size] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. - ^ 0! Item was added: + ----- Method: SequenceableCollection>>findFirst:ifNone: (in category 'enumerating') ----- + findFirst: aBlock ifNone: anotherBlock + + ^ self findFirst: aBlock startingAt: 1 ifNone: anotherBlock! Item was added: + ----- Method: SequenceableCollection>>findFirst:startingAt: (in category 'enumerating') ----- + findFirst: aBlock startingAt: minIndex + + ^ self findFirst: aBlock startingAt: minIndex ifNone: [0]! Item was added: + ----- Method: SequenceableCollection>>findFirst:startingAt:ifNone: (in category 'enumerating') ----- + findFirst: aBlock startingAt: minIndex ifNone: anotherBlock + "Return the index of my first element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + index := minIndex - 1. + [(index := index + 1) <= self size] whileTrue: + [(aBlock value: (self at: index)) ifTrue: [^index]]. + ^ anotherBlock value! Item was changed: ----- Method: SequenceableCollection>>findLast: (in category 'enumerating') ----- findLast: aBlock - "Return the index of my last element for which aBlock evaluates as true." + ^ self findLast: aBlock startingAt: 1! - | index | - index := self size + 1. - [(index := index - 1) >= 1] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. - ^ 0! Item was added: + ----- Method: SequenceableCollection>>findLast:ifNone: (in category 'enumerating') ----- + findLast: aBlock ifNone: anotherBlock + + ^ self findLast: aBlock startingAt: 1 ifNone: anotherBlock! Item was changed: ----- Method: SequenceableCollection>>findLast:startingAt: (in category 'enumerating') ----- + findLast: aBlock startingAt: minIndex - findLast: aBlock startingAt: i - "Return the index of my last element with index >= i for which aBlock evaluates as true." + ^ self findLast: aBlock startingAt: minIndex ifNone: [0]! - | index | - index := self size + 1. - [(index := index - 1) >= i] whileTrue: - [(aBlock value: (self at: index)) ifTrue: [^index]]. - ^ 0! Item was added: + ----- Method: SequenceableCollection>>findLast:startingAt:ifNone: (in category 'enumerating') ----- + findLast: aBlock startingAt: minIndex ifNone: anotherBlock + "Return the index of my last element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock." + + | index | + index := self size + 1. + [(index := index - 1) >= minIndex] whileTrue: + [(aBlock value: (self at: index)) ifTrue: [^index]]. + ^ anotherBlock value!

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The Inbox: Collections-ct.871.mcz
by commits＠source.squeak.org 07 Apr '22

07 Apr '22

A new version of Collections was added to project The Inbox: http://source.squeak.org/inbox/Collections-ct.871.mcz ==================== Summary ==================== Name: Collections-ct.871 Author: ct Time: 30 December 2019, 3:06:02.364602 pm UUID: 235b9546-6ad3-b547-8661-38c5f2a98374 Ancestors: Collections-nice.868 Refactor CharacterClass >> #constantNames: Use reflection instead of hardcoding all names. With this change, further characters such as Character arrowLeft are printed legibly. =============== Diff against Collections-nice.868 =============== Item was changed: ----- Method: Character class>>constantNames (in category 'private') ----- constantNames + ^ self class methodsInCategory: #'accessing untypeable characters'! - ^ #( backspace cr delete escape lf null newPage space tab ).!

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The Trunk: System-mt.1018.mcz
by commits＠source.squeak.org 19 Jan '22

19 Jan '22

Marcel Taeumel uploaded a new version of System to project The Trunk: http://source.squeak.org/trunk/System-mt.1018.mcz ==================== Summary ==================== Name: System-mt.1018 Author: mt Time: 16 April 2018, 10:31:28.239614 am UUID: e0350560-a5a5-5a40-b31b-d13f55162021 Ancestors: System-mt.1017 #setAuthorInitials: -> #authorInitials: =============== Diff against System-mt.1017 =============== Item was changed: ----- Method: SmalltalkImage>>openSourceFiles (in category 'sources, changes log') ----- openSourceFiles self imageName = LastImageName ifFalse: ["Reset the author initials to blank when the image gets moved" LastImageName := self imageName. + Utilities authorInitials: '']. - Utilities setAuthorInitials: '']. FileDirectory openSources: self sourcesName andChanges: self changesName forImage: LastImageName. SourceFileArray install!

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