Escaping $ to interpolate variables in L"..."

[jebej]

Would it make sense (or would it be even possible) to allow "escaping" $, either with a double $$ or something else, to allow interpolation in L"..." strings? It would be convenient instead of having to fall back to using latexstring and needing to escape every $ and \.

[stevengj]

It's certainly technically possible, but you'd need to find something that doesn't conflict with LaTeX.

I guess we could use \$, no, that is used for literal dollar signs in LaTeX equations.

[BeastyBlacksmith]

Well, you can use $ for interpolate and \ for escaping and writing \$ (in the final LaTeX string) would then be needed to be written as \\\$ (like escaping in the shell). But the L string was intended such, that you don't need to escape \ since it is so common in latex.
So maybe # would be better suited as escape character, then \$ would needed to be written as \#$.

[stillyslalom]

Another option would be extending @sprintf to allow its first argument to be a LaTeXString, with % as the interpolation/formatting character as usual. Compare:

latexstring("an equation: \$ $(round(c[1], digits=3)) + $(round(c[2], digits=3)) \\alpha^2 \$")

vs

@sprintf(L"an equation: $ %0.3f + %0.3f \alpha^2 $", c...)

[stillyslalom]

@sprintf needs a static format string (ref. JuliaLang/julia#29278), so the above syntax wouldn't work. It works as expected with Formatting.format, though:

julia> s1 = L"an equation: $ {:.3f} + {:.3f} \alpha^2 $"
L"an equation: $ {:.3f} + {:.3f} \alpha^2 $"

julia> format(s1, 1, 2)
"an equation: \$ 1.000 + 2.000 \\alpha^2 \$"

[stevengj]

You can always just use an ordinary string and backslash-escape any backslashes and dollar signs…

[stillyslalom]

Of course, but I'd prefer to use LaTeXStrings, which are cleaner and more convenient than the backslash-escape alternative. This sort of behavior comes up all the time when creating plot labels/titles/annotations which include calculated coefficients.

[stevengj]

We could use %$, since that is a comment in LaTeX and is unlikely to appear in normal text, but it is a bit ugly. Any other ideas?

[Moelf]

fonsp/Pluto.jl#313

I hit the symptom of this in Pluto when trying to interpolate in md""",

[stillyslalom]

@Moelf I think this is an issue on Markdown's end. You can work around your issue by directly accessing the string field:

julia> using Markdown, LaTeXStrings

julia> ls = L"y = mx + b";

julia> md"$(ls.s)"
"\$y = mx + b\$"

[Moelf]

@stillyslalom I don't know what customize the behavior when interpolated in string, but IF it is customizable (and be different from what print does on the type), then it should be customized in LaTeXString not in Markdown right?

[stillyslalom]

@Moelf To avoid the dependence of Markdown.jl (which is a stdlib package) upon LaTeXStrings.jl (which is not), it would need to be implemented here (or in a shim package), but that's entirely distinct from the issue at hand. It's probably best to open a new issue.

[Moelf]

I think I mis-read what this issue is about, oops, sry about the noise.