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##### LM #####
# 2010: I'm not sure what the following means.
#
# Local commit:
# -clears reparse flags underneath
# -must be possible to backtrack after
# Global commit (revertOn)
# -clears all reparse flags
# -must be possible to backtrack after
# Global commit (!revertOn)
# -clears all reparse flags
# -clears all 'parsed' reverse code
# -clears all reverse code
# -clears all alg structures
#
# This test shows that a global commit with revertOn correctly does not clear
# 'parsed' items because it must entertain the possibility of backtracking.
lex
ignore /[\t\n ]+/
literal '^', '|', '-', ',', ':', '!', '?', '.'
literal '(', ')', '{', '}', '*', '&', '+'
literal '--', ':>', ':>>', '<:', '->', '**'
token word /[a-zA-Z_][a-zA-Z0-9_]*/
token uint /[0-9]+/
end
def expression [term expression_op*]
def expression_op
['|' term]
| ['&' term]
| ['-' term]
| ['--' term]
def term [factor_rep term_rest]
# This list is done manually to get shortest match.
def term_rest
[]
| [term_op term_rest]
def term_op
[factor_rep]
| ['.' factor_rep]
| [':>' factor_rep]
| [':>>' factor_rep]
| ['<:' factor_rep]
def factor_rep
[factor_neg factor_rep_op*]
def factor_rep_op
['*']
| ['**']
| ['?']
| ['+']
| ['{' factor_rep_num '}']
| ['{' ',' factor_rep_num '}']
| ['{' factor_rep_num ',' '}']
| ['{' factor_rep_num ',' factor_rep_num '}']
def factor_rep_num [uint]
def factor_neg
['!' factor_neg]
| ['^' factor_neg]
| [factor]
def factor
[alphabet_num]
| [word]
| ['(' expression ')']
def alphabet_num
[uint]
def suint
i: int
[uint]
def sub
[suint* '*']
token item
S: sub
/[0-9]+/
{
M: str = input.pull(match_length)
parse_stop S: sub[input]
input.push( make_token( typeid<item> M S ) )
}
def stuff
[item* '!']
| [sub]
parse S: stuff[ stdin ]
print_xml( S )
print( '\n' )
##### IN #####
1 2 3 * !
##### EXP #####
<stuff><_repeat_item><item>1</item></_repeat_item><_literal_000d>!</_literal_000d></stuff>
|
