The order of alternatives in a "|" alternation construction _definitely_
matters, and always has, and matters for any PEG based grammar, for
sure, part of how a PEG works. And yeah, the order of alternatives in an
alternation construction ("|") is basically the (only) way to try and
set 'precedence' in a PEG.
The order of the rules themselves does not (generally? I think ever?)
make a difference in the parsing.
On 9/22/2012 1:59 PM, Joey Coyle wrote:
> Hi,
>
> Using 1.4
>
> The following doesn't work, but in the :number rule, if I invert integer and
> decimal, then it does work. The odd thing, is I have seen examples, like on
> the powerpoint presentation from the main website where they put integer
> first. Has Parslet changed since that presentation was made?
>
> thanks,
> joey
>
> class Mini < Parslet::Parser
> rule(:integer) { match('[0-9]').repeat(1) }
> rule(:decimal) { integer >> str('.') >> integer }
> rule(:number) { integer | decimal }
> root :number
> end
>
> puts Mini.new.parse("13.2432")
>
