Re: LPEG > 0.10 regression: 'B' (pattern may not have fixed length)

[Daurnimator <quae@...>]

On 30 May 2015 at 11:31, Daurnimator <quae@daurnimator.com> wrote:
> Trying to use Peter Odding's lxsh
> Issue has been filed for a while over there:
> https://github.com/xolox/lua-lxsh/issues/5
> But this should probably be fixed in LPEG itself?
>
>
> The below works fine with lpeg 0.10:
>
>> lpeg = require"lpeg"
>> D = lpeg.R'09'
>> BB = lpeg.B(-D, 1)
> stdin:1: bad argument #1 to 'B' (pattern may not have fixed length)

Today I finally got around to looking at this again.
I was working on updating peter odding's lxsh module for lua 5.3
https://github.com/daurnimator/lua-lxsh
And found that in lpeg 1.0 some of the tests fail (they passed in lpeg 0.10).

To get things working, I had to force a check for the length via a lookahead.
See https://github.com/daurnimator/lua-lxsh/commit/b620081cb8644e577f7f642d482087e3a0d366ba