New symbols request

[vaibhav423]

these symbols are not rendered
\xrightarrow[A]{B}
\boxed{43}
\mathrm{~N}
\underset{bottom}{top}
\overset{top_text}{main_symbol}

expected output : attached in image
got : error

This is utftex version 1.17
Powered by libtexprintf 1.31

[bartp5]

Thanks. I need to think a bit about how to add these things. All these constructs can be achieved in some other way with libtexprintf as is. So all this could be achieved using some sort of preprocessor mapping these commands to existing ones. The way I am doing it now, I cannot keep up with all possible latex commands used in the wild. So I need to rethink preprocessing of input strings a bit.

[vaibhav423]

instead of throwing error for the symbols, is it possible to show , some sort of fallback text for example if due to some reason , implementation of \xrightarrow[A]{B} is not possible simply show it like , A —> B or maybe just leave it like \xrightarrow[A]{B} , because some time, for example just because of single missing symbol the entire line shows error in nvim .

[bartp5]

Not sure if showing half baked renderings is such a good idea. If there is a problem I think it is more useful to show the original input to the user. The user is more likely to interpret that correctly. This can easily be dealt with on the caller side.

[bartp5]

The new dev branch should support the things you request. Under the hood I build a macro system to implement some of the commands. in src/macros.h there are some macros defined and macros can be added. Example macros are:

	{"boxed", 		1,0,	"\\begin{array}{|c|} \\hline $(0) \\\\\\hline\\end{array}"},
	{"xrightarrow",	1,1,	"\\stackrel{\\underrightarrow{$(0)}}{%(0)}"},

these macros define \boxed and \xrightarrow. The two numbers are the number of mandatory and optional arguments. The final string is the replacement string. In the replacement strings one can use $(n) to substitute the nth mandatory argument (start counting at 0) and, likewise, %(n) refers to the optional arguments. Thus the \boxed macro wraps it single mandatory argument in an array environment to draw a box around it, and \xrightarrow wraps its arguments in a \stackrel combined with \underrightarrow.

[vaibhav423]

it's awesome bro!.

[bartp5]

I still had to do something to scale arrow accents with contents. I added a bit more sophisticated arrow drawing:

utftex '\xrightarrow[A]{abc}'
abc
——⮞
 A

This change affects other arrow accents too, like \vec, \Lvec, etc.