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|
#
# check options working
#
class Calcp
prechigh
left '*' '/'
left '+' '-'
preclow
convert
NUMBER 'Number'
end
options no_omit_action_call no_result_var
rule
target : exp | /* none */ { 0 } ;
exp : exp '+' exp { chk(val[0] + val[2]) }
| exp '-' exp { chk(val[0] - val[2]) }
| exp '*' exp { chk(val[0] * val[2]) }
| exp '/' exp { chk(val[0] / val[2]) }
| '(' { $emb = true } exp ')'
{
raise 'must not happen' unless $emb
val[2]
}
| '-' NUMBER { -val[1] }
| NUMBER
;
end
----header
class Number; end
----inner
def parse( src )
@src = src
do_parse
end
def next_token
@src.shift
end
def initialize
@yydebug = true
end
def chk( i )
# p i
i
end
----footer
$parser = Calcp.new
$test_number = 1
def chk( src, ans )
result = $parser.parse(src)
raise "test #{$test_number} failed" unless result == ans
$test_number += 1
end
chk(
[ [Number, 9],
[false, false],
[false, false] ], 9
)
chk(
[ [Number, 5],
['*', nil],
[Number, 1],
['-', nil],
[Number, 1],
['*', nil],
[Number, 8],
[false, false],
[false, false] ], -3
)
chk(
[ [Number, 5],
['+', nil],
[Number, 2],
['-', nil],
[Number, 5],
['+', nil],
[Number, 2],
['-', nil],
[Number, 5],
[false, false],
[false, false] ], -1
)
chk(
[ ['-', nil],
[Number, 4],
[false, false],
[false, false] ], -4
)
chk(
[ [Number, 7],
['*', nil],
['(', nil],
[Number, 4],
['+', nil],
[Number, 3],
[')', nil],
['-', nil],
[Number, 9],
[false, false],
[false, false] ], 40
)
|