[fasmg] Dual mode, nested comment blocks.

Code:

define comment? comment?

namespace comment?

        define ENDER

        calminstruction start? &line&
                take ENDER, line
                arrange line, =mvmacro ?, =comment?=.=intercept?
                assemble line
        end calminstruction

        calminstruction intercept?! &line&
                local ender, text, nested

                arrange ender, ENDER
                match , ender
                jyes default_close

        custom_close:
                arrange text, line
                stringify ender
                stringify text
                check ender = text
                jyes clear
                jump maybe_nested

        default_close:
                match =END? =COMMENT?, line
                jyes clear

        maybe_nested:
                match =COMMENT? nested?, line
                jno skip

                take ENDER, nested
        skip:
                exit

        clear:
                take , ENDER
                take ENDER, ENDER
                jyes skip

                arrange line, =mvmacro =comment?=.=intercept?, ?
                assemble line
        end calminstruction

        restore ENDER

end namespace

mvmacro comment?, comment?.start?

Dual mode in that it supports a comment terminator token and an "end comment" style termination.

Nesting because sources could be long.

Code:

comment
    any tokenizable source text
    comment
        nested text
    end comment
end comment

Code:

comment ~
    this block closes only on ~
    end comment is ordinary text here
~

Code:

comment End Comment
        ; even this works, lol!
        end comment
End Comment