struct TopDown::Parser::Fail
- TopDown::Parser::Fail
- Struct
- Value
- Object
Overview
Empty struct representing a parse failure.
When Parser.parse
is used,
if it fails, it break
the current sequence with a Fail
.
However when the method is surrounded by a block, the Fail
get returned.
In this case it recommended to use Parser.forward_fail
to break
again.
result = Array.new(3) do
parse("a")
end
typeof(result) # => Array(String) | TopDown::Parser::Fail
result = forward_fail(result)
typeof(result) # => Array(String)