Hello everyone,
I am having some trouble understanding leex behaviour. To give some context, I would like to create a parser for pgn files.
Here is some code to explain my problem.
I created the lexer file pgn_lexer.xrl with
% -- Definitions.
Definitions.
TAG = (\[[^\]]*\])+
COMMENT = ({[^}]*})+
WHITESPACE = [\s\t\n\r]
Rules.
{TAG} : {token, {tag, TokenLine, TokenChars}}.
{COMMENT} : {token, {comment, TokenLine, TokenChars}}.
{WHITESPACE}+ : skip_token.
Erlang code.
The important rule is for TAG
( \[ [^\]] * \] )+
I cannot understand why
iex> :pgn_lexer.string '[Tag1 "Value1"] [Tag2 "Value2"]{comment}'
{:ok,
[
{:tag, 1, '[Tag1 "Value1"]'},
{:tag, 2, '[Tag2 "Value2"]'},
{:comment, 2, '{comment}'}
], 2}
# This works has expected, it detects 2 tags
iex> :pgn_lexer.string '[Tag1 "Value1"][Tag2 "Value2"]{comment}'
{:ok, [{:tag, 1, '[Tag1 "Value1"][Tag2 "Value2"]'}, {:comment, 1, '{comment}'}],
1}
# This does not work, tag1 and tag2 are merged
Why do the tags need to be separated by a space?
Thanks for enlightments.
