PGML algebra mode doesn't respect number display format set in the Context

[dlglin]

Algebra mode in PGML seems to be hard-coded to use "%g" as the display format for numbers, which leads to some counterintuitive behaviour with MathObjects, particularly when a custom number format is set in the context.

Consider the following MWE:

DOCUMENT();

loadMacros("PGstandard.pl","MathObjects.pl","PGML.pl");

Context()->{format}{number} = "%d";
$x = Real(1234567);

BEGIN_PGML
[`[$x]`]

[:[$x]:]
END_PGML

ENDDOCUMENT();

In LaTeX mode it displays 1234567, but in algebra mode it converts to scientific notation. This doesn't seem like the desired behaviour if the author has explicitly set a number format for the MathObject.

Does it make sense to have PGML inherit the number format from the context? Is that even possible?

[dpvc]

This is by design. The algebra math notation is processed in a special Typeset context, which includes more operations and functions than the usual contexts. You can cause the algebra notation to use the current context by adding a star after the notation, as in

[:[$x]:]*

or provide a context in several other ways. See the wiki documentation for details.

You could probably also do something like

$context{Typeset} = Context("Typeset");
$context{Typeset}->{format}{number} = "%d";
Context("Numeric");

...

BEGIN_PGML
[:[$x]:]
END_PGML

though I haven't tried it to see. That should make PGML use your copy of the Typeset context, which you have altered to have the changed number format.