steve
/
factor
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Allow var names in ebnf but ignore them for now

db4
Chris Double 2008-03-30 19:01:47 +13:00
parent a23e0ce15c
commit 78633e03a0
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
extra/peg/ebnf/ebnf.factor
View File

@ -19,6 +19,7 @@ TUPLE: ebnf-repeat1 group ;
TUPLE: ebnf-optional group ;
TUPLE: ebnf-rule symbol elements ;
TUPLE: ebnf-action parser code ;
TUPLE: ebnf-var parser name ;
TUPLE: ebnf rules ;
C: <ebnf-non-terminal> ebnf-non-terminal
@ -34,6 +35,7 @@ C: <ebnf-repeat1> ebnf-repeat1
C: <ebnf-optional> ebnf-optional
C: <ebnf-rule> ebnf-rule
C: <ebnf-action> ebnf-action
C: <ebnf-var> ebnf-var
C: <ebnf> ebnf
: syntax ( string -- parser )
@ -79,6 +81,7 @@ C: <ebnf> ebnf
[ dup CHAR: * = ]
[ dup CHAR: + = ]
[ dup CHAR: ? = ]
[ dup CHAR: : = ]
} || not nip
] satisfy repeat1 [ >string <ebnf-non-terminal> ] action ;
@ -200,6 +203,7 @@ DEFER: 'choice'
: 'actioned-sequence' ( -- parser )
[
[ 'sequence' , "=>" syntax , 'action' , ] seq* [ first2 <ebnf-action> ] action ,
[ 'sequence' , ":" syntax , "a-zA-Z" range-pattern repeat1 [ >string ] action , ] seq* [ first2 <ebnf-var> ] action ,
'sequence' ,
] choice* ;
@ -270,6 +274,9 @@ M: ebnf-action (transform) ( ast -- parser )
[ parser>> (transform) ] keep
code>> string-lines [ parse-lines ] with-compilation-unit action ;
M: ebnf-var (transform) ( ast -- parser )
parser>> (transform) ;
M: ebnf-terminal (transform) ( ast -- parser )
symbol>> token sp ;