[metapost] make_text related scanning improvements

[Taco Hoekwater]

Hi,

> On 18 May 2018, at 11:15, Hans Hagen <j.hagen at xs4all.nl> wrote:
> 
> changing fundamentals like this nearly always have side effects ... you cannot always know how these tools are used (for decades) ... you solve one problem and introduces a new one .. such is the world of tex / mp

As the original ‘author’ of the reimplementation I can attest to that! 

It took half a dozen minor adjustments to the reimplementation just to make it compatible with pre-existing metapost source files, due to subtle differences between the Pascal and C handling of whitespace. I am not saying the code cannot be improved at all, but it seems likely that any changes at this point will have side-effects that break already existing metapost source files.

Best wishes,
Taco