Re: prettify-symbols-mode to handle "\alpha-\beta" ...

[Óscar Fuentes]

pietru@caramail.com writes:

> I am using prettify-symbols-mode for displaying greek command using
> the corresponding greek glyph when using mathematical expressions
> in texinfo.
>
> Here is an example
>
>   (push '("\\alpha" . ?α) prettify-symbols-alist)
>   (push '("\\beta" . ?β) prettify-symbols-alist)
>
> This works well when using "\alpha\beta", "\alpha - \beta" 
> But the expression fails when using "\alpha-\beta" or
> "\alpha_i", "\alpha_{ij}", "\beta^i", "\beta+\alpha".
> The expressions are all valid mathematical expressions
> when using tex.  
>
> Would you be so kind to update "prettify-symbols-mode"
> so the substitutions can become possible to handle.
>
> Does this require that SYMBOL in (SYMBOL . CHARACTER) be
> a regexp?

The docstring of prettify-symbols-alist says:

  Each element looks like (SYMBOL . CHARACTER), where the symbol
  matching SYMBOL (a string, not a regexp) will be shown as CHARACTER
  instead.

so no, SYMBOL *must* *not* be a regexp.

I can't reproduce the problem you are describing. After starting Emacs:

emacs -Q

if I evaluate this in *scratch*:

  (push '("\\alpha" . ?α) prettify-symbols-alist)

then open a .tex file, write \alpha_i, M-x prettify-symbols-alist, the
string is transformed to α_i.

Please note that the definition of SYMBOL depends on the major mode of
the buffer, so make sure that your current major mode is tex-mode.