Provide ability to plug in tokenizers to ebnf parsers

db4
Chris Double 2008-06-20 22:29:53 +12:00
parent 7239c4d79f
commit b6b5f12732
2 changed files with 44 additions and 7 deletions

View File

@ -11,6 +11,31 @@ IN: peg.ebnf
#! Given an EBNF word produced from EBNF: return the EBNF rule
"ebnf-parser" word-prop at ;
TUPLE: tokenizer any one many ;
: default-tokenizer ( -- tokenizer )
T{ tokenizer f
[ [ drop t ] satisfy ]
[ token ]
[ [ = ] curry satisfy ]
} ;
: parser-tokenizer ( parser -- tokenizer )
1quotation [ [ = ] curry satisfy ] dup tokenizer boa ;
: rule-tokenizer ( name word -- tokenizer )
rule parser-tokenizer ;
: tokenizer ( -- word )
\ tokenizer get [ default-tokenizer ] unless* ;
: reset-tokenizer ( -- )
default-tokenizer \ tokenizer set-global ;
: TOKENIZER:
scan search [ "Tokenizer not found" throw ] unless*
execute \ tokenizer set-global ; parsing
TUPLE: ebnf-non-terminal symbol ;
TUPLE: ebnf-terminal symbol ;
TUPLE: ebnf-foreign word rule ;
@ -344,7 +369,7 @@ M: ebnf-choice (transform) ( ast -- parser )
options>> [ (transform) ] map choice ;
M: ebnf-any-character (transform) ( ast -- parser )
drop any-char ;
drop [ tokenizer any>> call ] box ;
M: ebnf-range (transform) ( ast -- parser )
pattern>> range-pattern ;
@ -435,7 +460,7 @@ M: ebnf-var (transform) ( ast -- parser )
parser>> (transform) ;
M: ebnf-terminal (transform) ( ast -- parser )
symbol>> [ token ] keep [ = ] curry satisfy 2choice ;
symbol>> [ tokenizer one>> call ] curry box ;
M: ebnf-foreign (transform) ( ast -- parser )
dup word>> search
@ -476,10 +501,22 @@ M: ebnf-non-terminal (transform) ( ast -- parser )
parse-result-ast transform dup dup parser [ main swap at compile ] with-variable
[ compiled-parse ] curry [ with-scope ] curry ;
: [EBNF "EBNF]" parse-multiline-string ebnf>quot nip parsed ; parsing
: [EBNF
scan {
{ "+" [ scan-word execute "" swap ] }
[ " " append default-tokenizer ]
} case \ tokenizer [
[ "EBNF]" parse-multiline-string ] [ drop "" ] recover append ebnf>quot nip parsed
] with-variable ; parsing
: EBNF:
CREATE-WORD dup
";EBNF" parse-multiline-string
ebnf>quot swapd 1 1 <effect> define-declared "ebnf-parser" set-word-prop ; parsing
CREATE-WORD scan {
{ "+" [ scan-word execute "" swap ] }
[ " " append default-tokenizer ]
} case \ tokenizer [
dupd [ ";EBNF" parse-multiline-string ] [ drop "" ] recover append
ebnf>quot swapd 1 1 <effect> define-declared "ebnf-parser" set-word-prop
] with-variable ; parsing

View File

@ -8,7 +8,7 @@ IN: peg.javascript.tokenizer
USE: prettyprint
EBNF: tokenizer
EBNF: javascript-tokenizer
Letter = [a-zA-Z]
Digit = [0-9]
Digits = Digit+