Wouldn't it be convenient if you could do this:
msg := 'The number is ', number
instead of
msg := 'The number is ', number printString
Or even this:
msg := number, ' is the value you entered.'
instead of
msg := number printString, ' is the value you entered.'
This would require the comma method in Collection to act differently when the argument isn't a Collection and the Number class would need to add a comma method.
I'm pretty new at this, so maybe there are reasons this is done. Are there?
As some might guess, I'm used to the way Java automatically calls toString on things that aren't strings when one side of a concatenation is a String and the other isn't.
--- Mark Volkmann
Wouldn't it be convenient if you could do this:
msg := 'The number is ', number
msg := 'The number is {1} or else is {2}' format: { number. number2 }
Behaves this way and looks much better when you have multiple args.
Ramon Leon http://onsmaltalk.com
On 02.11.2008, at 12:49, Ramon Leon wrote:
Wouldn't it be convenient if you could do this:
msg := 'The number is ', number
msg := 'The number is {1} or else is {2}' format: { number. number2 }
Behaves this way and looks much better when you have multiple args.
Very good point - this format is also better for translating.
It's probably good practice to use "," only for debug output - and there it is useful because it saves keystrokes.
- Bert -
Mark Volkmann wrote:
Wouldn't it be convenient if you could do this:
msg := 'The number is ', numberinstead of
msg := 'The number is ', number printStringOr even this:
msg := number, ' is the value you entered.'instead of
msg := number printString, ' is the value you entered.'This would require the comma method in Collection to act differently when the argument isn't a Collection and the Number class would need to add a comma method.
I'm pretty new at this, so maybe there are reasons this is done. Are there?
In general concatenation isn't the most efficient means to assemble a string. I always build my strings using a stream, and to help readability I have defined my extension #<< to stream.
out := String new writeStream.
out << 'The number is' << number
^ out contents
my definition of #<< calls putOn: on each item, and putOn: does ensure that numbers are converted to strings first.
== To avail yourself of this extension, execute (if you have installer loaded)
Installer mantis ensureFix: 7219.
best regards
Keith.
Am 02.11.2008 um 12:34 schrieb Mark Volkmann mark@ociweb.com:
Wouldn't it be convenient if you could do this:
msg := 'The number is ', number
instead of
msg := 'The number is ', number printString
Or even this:
msg := number, ' is the value you entered.'
instead of
msg := number printString, ' is the value you entered.'
This would require the comma method in Collection to act differently when the argument isn't a Collection and the Number class would need to add a comma method.
It's convenient indeed but could lead to surprises for non-string collections. Also, there is a school of thinking that abhors any "magic". It does change the semantics of #, depending on the passed object, so there is some reason nor to do it.
I personally find it useful, and IIRC Croquet implements String>>, as "^super , anObject asString."
- Bert -
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Bert Freudenberg -
Keith Hodges -
Mark Volkmann -
Ramon Leon