@@ -70,107 +70,12 @@ into effect for the Regex:
7070
7171= SUBTITLE Group of named regexes that form a formal grammar
7272
73- class Grammar is Cursor { }
74-
75- C < Grammar > is the superclass that classes automatically get when they are
76- declared with the C < grammar > keyword instead of C < class > . Grammars should
77- only be used to parse text; if you wish to extract complex data, an L < action
78- object|/language/grammars#Action_Objects > is recommended to be used in
73+ L < Grammar|/type/Grammar > is the superclass that classes automatically get when
74+ they are declared with the C < grammar > keyword instead of C < class > . Grammars
75+ should only be used to parse text; if you wish to extract complex data, an
76+ L < action object|/language/grammars#Action_Objects > is recommended to be used in
7977conjunction with the grammar.
8078
81- = begin code :allow<B L>
82- B < grammar > CSV {
83- token TOP { [ <line> \n? ]+ }
84- token line {
85- ^^ # Beginning of a line
86- <value>* % \, # Any number of <value>s with commas in between them
87- $$ # End of a line
88- }
89- token value {
90- [
91- | <-[",\n]> # Anything not a double quote, comma or newline
92- | <quoted-text> # Or some quoted text
93- ]* # Any number of times
94- }
95- token quoted-text {
96- \"
97- [
98- | <-["\\]> # Anything not a " or \
99- | '\"' # Or \", an escaped quotation mark
100- ]* # Any number of times
101- \"
102- }
103- }
104-
105- say "Valid CSV file!" if CSV.L < parse > ( q:to/EOCSV/ );
106- Year,Make,Model,Length
107- 1997,Ford,E350,2.34
108- 2000,Mercury,Cougar,2.38
109- EOCSV
110- = end code
111-
112- = head2 Methods
113-
114- = head3 method parse
115-
116- method parse($str, :$rule = 'TOP', :$actions) returns Match:D
117-
118- Matches the grammar against C < $str > , using C < $rule > as the starting rule,
119- optionally applying C < $actions > as its actions object.
120-
121- This will fail if the grammar does not parse the I < entire > string. If a
122- parse of only a part of the string is desired, use L < subparse > .
123-
124- The method returns the resulting L < Match > object and also sets the caller's
125- C < $/ > variable to the Match object.
126-
127- = begin code :allow<B>
128- say CSVB < .parse > ( q:to/EOCSV/ );
129- Year,Make,Model,Length
130- 1997,Ford,E350,2.34
131- 2000,Mercury,Cougar,2.38
132- EOCSV
133- = end code
134-
135- This outputs:
136-
137- ｢Year,Make,Model,Length
138- 1997,Ford,E350,2.34
139- 2000,Mercury,Cougar,2.38
140- ｣
141- line => ｢Year,Make,Model,Length｣
142- value => ｢Year｣
143- value => ｢Make｣
144- value => ｢Model｣
145- value => ｢Length｣
146- line => ｢1997,Ford,E350,2.34｣
147- value => ｢1997｣
148- value => ｢Ford｣
149- value => ｢E350｣
150- value => ｢2.34｣
151- line => ｢2000,Mercury,Cougar,2.38 ｣
152- value => ｢2000｣
153- value => ｢Mercury｣
154- value => ｢Cougar｣
155- value => ｢2.38 ｣
156-
157- = head3 method subparse
158-
159- method subparse($str, :$rule = 'TOP', :$actions) returns Match:D
160-
161- Matches the grammar against C < $str > , using C < $rule > as the starting rule,
162- optionally applying C < $actions > as its actions object.
163-
164- Unlike L < parse > , C < subparse > will allow the grammar to match only part of
165- the supplied string.
166-
167- = head3 method parsefile
168-
169- method parsefile(Str(Cool) $filename, *%opts) returns Match:D
170-
171- Parses the contents of the file C < $filename > with the L < parse > method,
172- passing any named options in C < %opts > .
173-
17479= head1 Action Objects
17580
17681A successful grammar match gives you a parse tree of L < Match|/type/Match >
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