Format escape sequences %c and %r are confusing

[tothtamas28]

There seems to be little reason to use these escape sequences directly, as for a terminal "foo", %i is implicitly %cfoo%r, i.e. coloring is handled automatically.

Preliminaries

One situation in which it can be useful though is to give some color to otherwise uncolored non-terminals.

module COLORS
    syntax Foo ::= "foo" Bar "qux" [symbol(foo), format(%1 %c%2%r %3), colors(green, purple, yellow)]
    syntax Bar ::= "bar" "baz"     [symbol(bar)]
endmodule\

Here, a reasonable, modular behavior would be to either

1. override all coloring for Bar to purple, or
2. override the default color for Bar to purple, or
3. do nothing.

The problem

However, in the above example

echo 'Lblfoo{}(Lblbar{}())' | kprint colors-kompiled /dev/stdin

produces

In cases (1) and (2) bar baz should be purple, and in (3) it should be white.

Possible solutions

1. Remove the special meaning of these escape sequences. This either requires dropping them from KORE as well, or some extra processing in ModuleToKore (basically replace %{c,r} by {c,r}).
2. Come up with a more modular semantics for coloring.