>When I  evaluate:
>   parser :=  PEGParser parserPEG parse: 'Grammar' stream: PEGParser 
grammarEmailAddress actor: PEGParserParser new.

>I get:  KeyNotFound: key 'quotedstring' not found in Dictionary

>How am I  supposed to debug that to find the typo in my giant string above?!

Hi Sean,

Your error is saying is that there is no key called 'quotedstring' in 
the dictionary in the grammar ivar of your parser.

In each parser is a grammar ivar. It contains a dictionary. The values 
of the dictionary are graphs of compiled blocks. Each node of the graph 
is a block with arguments that are blocks that have arguments that are 
blocks, etc. It's a graph of compiled blocks.

Try this. Add in PEGParser class.

grammar3Names
" a grammar to create a parser to sort three names as per page 24 of 
Grune's book Parsing Techniques (1990)"

^'Sentence    <-    NAME

NAME    <-  "tom" / "dick" / "harry"
'

Now execute this.

(PEGParser parserBootstrap) parse: 'Grammar' stream:  PEGParser 
grammar3Names reading actor: PEGParserGenerator new.

That will show you the code that will create the dictionary in the 
grammar ivar. Now make a change.

myparser := (PEGParser parserBootstrap) parse: 'Grammar' stream:  
PEGParser grammar3Names reading actor: PEGParserParser new.

You generated the parser, not the code for the parser.

To use the parser.

myparser parse: 'Sentence' stream: 'harry' reading actor: nil

Now let's look at the same thing in three ways.

PEGParser>>#grammarPEG   this is the grammar
PEGParser>>#parserBootstrap   this is the code generated by the 
PEGParserGenerator from grammarPEG
PEGParser>>#parserPEG  this is the parser returned by PEGParserParser 
from grammarPEG

You will see that PEGParser parserBootstrap and PEGParser parserPEG are 
interchangeable anywhere. In fact, if the goal is to populate the 
grammar ivar with a dictionary to make a parser, then #parserPEG starts 
to grate on one's nerves, because you already have what you need in the 
grammar ivar by evaluating PEGParser parserBootstrap. #parserPEG 
compiles the grammarPEG using PEGParserParser into the grammar ivar to 
make a parser, but it's the exact same as what was already there. It's 
irritating.

I'll release some examples in a package called Xtreamly some time before 
Christmas to help start understanding Xtreams-Parsing.

HTH,
Chris

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