# More syntax: tips and tricks
# Comments
Comments are marked with '#'. Everything from # to the end of a line is
ignored:
expression -> number "+" number # sum of two numbers
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# Charsets
You can use valid RegExp charsets in a rule (unless you're using a tokenizer):
not_a_letter -> [^a-zA-Z]
The . character can be used to represent any character.
# Case-insensitive string literals
You can create case-insensitive string literals by adding an i after the
string literal:
cow -> "cow"i # matches CoW, COW, and so on.
Note that if you are using a lexer, your lexer should use the i flag in its
regexes instead. That is, if you are using a lexer, you should not use the
i suffix in nearley.