From c455336da6012d85cfc4b182b331d0f00e4e4e3f Mon Sep 17 00:00:00 2001
From: Chris Double <chris.double@double.co.nz>
Date: Wed, 28 Nov 2007 12:50:04 +1300
Subject: [PATCH] Add action rule to ebnf
---
extra/peg/ebnf/ebnf.factor | 34 ++++++++++++++++++++++++++++------
1 file changed, 28 insertions(+), 6 deletions(-)
diff --git a/extra/peg/ebnf/ebnf.factor b/extra/peg/ebnf/ebnf.factor
index 8726581488..06e3c15163 100644
--- a/extra/peg/ebnf/ebnf.factor
+++ b/extra/peg/ebnf/ebnf.factor
@@ -1,6 +1,6 @@
! Copyright (C) 2007 Chris Double.
! See http://factorcode.org/license.txt for BSD license.
-USING: kernel parser words arrays strings math.parser sequences namespaces peg ;
+USING: kernel parser words arrays strings math.parser sequences vectors namespaces peg ;
IN: peg.ebnf
TUPLE: ebnf-non-terminal symbol ;
@@ -9,6 +9,7 @@ TUPLE: ebnf-choice options ;
TUPLE: ebnf-sequence elements ;
TUPLE: ebnf-repeat0 group ;
TUPLE: ebnf-rule symbol elements ;
+TUPLE: ebnf-action quot ;
TUPLE: ebnf rules ;
C: <ebnf-non-terminal> ebnf-non-terminal
@@ -17,6 +18,7 @@ C: <ebnf-choice> ebnf-choice
C: <ebnf-sequence> ebnf-sequence
C: <ebnf-repeat0> ebnf-repeat0
C: <ebnf-rule> ebnf-rule
+C: <ebnf-action> ebnf-action
C: <ebnf> ebnf
GENERIC: ebnf-compile ( ast -- quot )
@@ -62,6 +64,19 @@ M: ebnf-rule ebnf-compile ( ast -- quot )
ebnf-rule-elements ebnf-compile , \ define-compound ,
] [ ] make ;
+M: ebnf-action ebnf-compile ( ast -- quot )
+ [
+ ebnf-action-quot , \ action ,
+ ] [ ] make ;
+
+M: vector ebnf-compile ( ast -- quot )
+ [
+ [ ebnf-compile % ] each
+ ] [ ] make ;
+
+M: f ebnf-compile ( ast -- quot )
+ drop [ ] ;
+
M: ebnf ebnf-compile ( ast -- quot )
[
ebnf-rules [
@@ -75,7 +90,7 @@ DEFER: 'rhs'
CHAR: a CHAR: z range repeat1 [ >string <ebnf-non-terminal> ] action ;
: 'terminal' ( -- parser )
- "\"" token hide [ CHAR: " = not ] satisfy repeat1 "\"" token hide 3array seq [ first >string <ebnf-terminal> ] action ;
+ "'" token hide [ CHAR: ' = not ] satisfy repeat1 "'" token hide 3array seq [ first >string <ebnf-terminal> ] action ;
: 'element' ( -- parser )
'non-terminal' 'terminal' 2array choice ;
@@ -94,13 +109,20 @@ DEFER: 'rhs'
"}" token sp hide
3array seq [ first <ebnf-repeat0> ] action ;
+: 'action' ( -- parser )
+ "=>" token hide
+ "[" token sp hide
+ "]." token ensure-not [ drop t ] satisfy 2array seq [ first ] action repeat1 [ >string ] action
+ "]" token "." token ensure 2array seq sp hide
+ 4array seq [ "[ " swap first append " ]" append eval <ebnf-action> ] action ;
+
: 'rhs' ( -- parser )
'repeat0'
'sequence'
'choice'
- 'element'
- 4array choice ;
-
+ 'element'
+ 4array choice 'action' sp optional 2array seq ;
+
: 'rule' ( -- parser )
'non-terminal' [ ebnf-non-terminal-symbol ] action
"=" token sp hide
@@ -117,4 +139,4 @@ DEFER: 'rhs'
f
] if* ;
-: <EBNF "EBNF>" parse-tokens "" join ebnf>quot call ; parsing
\ No newline at end of file
+: <EBNF "EBNF>" parse-tokens " " join dup . ebnf>quot call ; parsing
\ No newline at end of file