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From 279644fb0b99dfb07ceaf713ca610e043131c6f4 Mon Sep 17 00:00:00 2001
From: Alex Merry <dev@randomguy3.me.uk>
Date: Fri, 2 Aug 2013 21:24:08 +0100
Subject: [PATCH 4/4] Tidy up and document bison decls in tikzparser.ym
---
tikzit/src/common/tikzparser.ym | 48 ++++++++++++++++++++++++++++-------------
1 file changed, 33 insertions(+), 15 deletions(-)
diff --git a/tikzit/src/common/tikzparser.ym b/tikzit/src/common/tikzparser.ym
index 6eea833..9901f79 100644
--- a/tikzit/src/common/tikzparser.ym
+++ b/tikzit/src/common/tikzparser.ym
@@ -18,11 +18,25 @@
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-#import "Edge.h"
-
%}
+%error-verbose
+/* enable maintaining locations for better error messages */
+%locations
+/* the name of the header file */
+%defines "common/tikzparser.h"
+/* make it re-entrant (no global variables) */
+%pure-parser
+/* We use a pure (re-entrant) lexer. This means yylex
+ will take a void* (opaque) type to maintain its state */
+%lex-param {void *scanner}
+/* Since this parser is also pure, yyparse needs to take
+ that lexer state as an argument */
+%parse-param {void *scanner}
+
+/* things required to use the parser (will go in the header);
+ in particular, declarations/imports for types in the %union
+ must go here */
%code requires {
#import <Foundation/Foundation.h>
@class TikzGraphAssembler;
@@ -35,36 +49,40 @@ struct noderef {
};
}
-%defines "common/tikzparser.h"
-%pure-parser
-%locations
-%lex-param {void *scanner}
-%parse-param {void *scanner}
-%error-verbose
-
+/* possible data types for semantic values */
%union {
NSPoint pt;
NSString *nsstr;
GraphElementProperty *prop;
GraphElementData *data;
Node *node;
- struct noderef noderef; };
+ struct noderef noderef;
+}
-%{
-#import "TikzGraphAssembler+Parser.h"
+%code {
#import "GraphElementData.h"
#import "GraphElementProperty.h"
#import "Node.h"
+#import "Edge.h"
+
#import "tikzlexer.h"
+#import "TikzGraphAssembler+Parser.h"
+/* the assembler (used by this parser) is stored in the lexer
+ state as "extra" data */
#define assembler yyget_extra(scanner)
+
+/* pass errors off to the assembler */
void yyerror(YYLTYPE *yylloc, void *scanner, const char *str) {
[assembler reportError:str atLocation:yylloc];
}
-%}
+}
+/* yyloc is set up with first_column = last_column = 1 by default;
+ however, it makes more sense to think of us being "before the
+ start of the line" before we parse anything */
%initial-action {
yylloc.first_column = yylloc.last_column = 0;
-};
+}
%token BEGIN_TIKZPICTURE_CMD "\\begin{tikzpicture}"
--
2.11.0
|
