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|
#
#
# Converting Array-like string into Ruby's Array, version 2.
# This grammar uses no_result_var.
class ArrayParser2
options no_result_var
rule
array : '[' contents ']' { val[1] }
| '[' ']' { [] }
contents: ITEM { val }
| contents ',' ITEM { val[0].push val[2]; val[0] }
end
---- inner
def parse(str)
@str = str
yyparse self, :scan
end
def scan
str = @str.strip
until str.empty?
case str
when /\A\s+/
str = $'
when /\A\w+/
yield [:ITEM, $&]
str = $'
else
c = str[0,1]
yield [c, c]
str = str[1..-1]
end
end
yield [false, '$'] # is optional from Racc 1.3.7
end
def next_token
@q.shift
end
---- footer
if $0 == __FILE__
src = <<EOS
[
a, b, c,
d,
e ]
EOS
puts 'parsing:'
print src
puts
puts 'result:'
p ArrayParser2.new.parse(src)
end
|
