1 files changed, 66 insertions, 0 deletions
diff --git a/src/examples/ebnftest.py b/src/examples/ebnftest.py
new file mode 100644
index 0000000..f0ce654
--- /dev/null
+++ b/src/examples/ebnftest.py
@@ -0,0 +1,66 @@
+print 'Importing pyparsing...'
+from pyparsing import *
+
+print 'Constructing EBNF parser with pyparsing...'
+import ebnf
+import sets
+
+
+grammar = '''
+syntax = (syntax_rule), {(syntax_rule)};
+syntax_rule = meta_identifier, '=', definitions_list, ';';
+definitions_list = single_definition, {'|', single_definition};
+single_definition = syntactic_term, {',', syntactic_term};
+syntactic_term = syntactic_factor,['-', syntactic_factor];
+syntactic_factor = [integer, '*'], syntactic_primary;
+syntactic_primary = optional_sequence | repeated_sequence |
+  grouped_sequence | meta_identifier | terminal_string;
+optional_sequence = '[', definitions_list, ']';
+repeated_sequence = '{', definitions_list, '}';
+grouped_sequence = '(', definitions_list, ')';
+(* 
+terminal_string = "'", character - "'", {character - "'"}, "'" |
+  '"', character - '"', {character - '"'}, '"';
+ meta_identifier = letter, {letter | digit};
+integer = digit, {digit}; 
+*)
+'''
+
+table = {}
+#~ table['character'] = Word(printables, exact=1)
+#~ table['letter'] = Word(alphas + '_', exact=1)
+#~ table['digit'] = Word(nums, exact=1)
+table['terminal_string'] = sglQuotedString
+table['meta_identifier'] = Word(alphas+"_", alphas+"_"+nums)
+table['integer'] = Word(nums)
+
+print 'Parsing EBNF grammar with EBNF parser...'
+parsers = ebnf.parse(grammar, table)
+ebnf_parser = parsers['syntax']
+
+commentcharcount = 0
+commentlocs = sets.Set()
+def tallyCommentChars(s,l,t):
+    global commentcharcount,commentlocs
+    # only count this comment if we haven't seen it before
+    if l not in commentlocs:
+        charCount = ( len(t[0]) - len(filter(str.isspace, t[0])) )
+        commentcharcount += charCount
+        commentlocs.add(l)
+    return l,t
+
+#ordinarily, these lines wouldn't be necessary, but we are doing extra stuff with the comment expression
+ebnf.ebnfComment.setParseAction( tallyCommentChars )
+ebnf_parser.ignore( ebnf.ebnfComment )
+
+print 'Parsing EBNF grammar with generated EBNF parser...\n'
+parsed_chars = ebnf_parser.parseString(grammar)
+parsed_char_len = len(parsed_chars)
+
+print "],\n".join(str( parsed_chars.asList() ).split("],"))
+
+#~ grammar_length = len(grammar) - len(filter(str.isspace, grammar))-commentcharcount
+
+#~ assert parsed_char_len == grammar_length
+
+print 'Ok!'