bug#62536: 30.0.50; Can we add """ ... """ electric pair in elixir, just like python

[Wilhelm Kirschbaum]

Hi João,

> > I had a look and don't see how without changing elec-pair.el 
> > that
> > there
> > is a more elegant way to do this.  I am happy with the current
> > patches
> > to be installed and then perhaps if there is a better way we 
> > can
> > apply
> > it to both python-mode and elixir-ts-mode later.
>
> It seems what you are trying to do is actually a functionality
> of electric-layout-mode,  right? It's creating newlines between
> two sets of '"""' so that if the user types one newline between
> them, then one extra newline is inserted after and the line is
> indented one level deeper than the '"""'.
>
> If so, it would seem like 'electric-layout-rules' would be a 
> good
> match.  The behaviour would happen _only_ if the user has
> electric-layout-mode, which is the standard Emacs mode for
> controlling this kind of electricity.  The last paragraph
> of the docstring of 'electric-layout-rules' seems to describe
> a powerful enough mechanism to do achieve what the custom
> psif does.
>
> João

The custom psif is not for the newline, but for pairing up the 
triple
quotes `"""` with another set of tripe quotes when 
electric-pair-mode is
enabled.  The newline is for keeping the syntax valid in elixir,
otherwise the font and navigation breaks because `""""""` is not 
valid
Elixir syntax and the tree-sitter grammar really does not like it.

Unless electric-indent-chars can identify the triple quotes, we 
need a
custom psif regardless of other functionality, but I don't see 
this
option.  Maybe I am wrong and you can point me to this feature?

If it does not make sense to add the newline as this might not be
expected behaviour when electric-layout-mode is not enabled, we 
can add
a check before inserting the newline?  I don't know if many people 
using
elixir-ts-mode will know about the electric layout mode and might 
get annoyed with
electric-pair-mode for heredocs ( tripple quote pairs ).