nomsu/compatibility/2.nom

#!/usr/bin/env nomsu -V2.3.4.3
use "core"
use "compatibility/compatibility.nom"

upgrade %tree to "2" as:
    unless (%tree is "Action" syntax tree): return
    if (%tree.stub is "if % % else %"):
        %true_body = (%tree.3 upgraded)
        unless (%true_body is "Block" syntax tree):
            %true_body = (=lua "Block(\%true_body.source, \%true_body)")
        %false_body = (%tree.5 upgraded)
        unless (%false_body is "Block" syntax tree):
            %false_body = (=lua "Block(\%false_body.source, \%false_body)")
        return (..)
            \(if %cond %true_body else %false_body)
            ..with vars {..}
                cond:%tree.2 upgraded, true_body:%true_body, false_body:%false_body
    
    %need_blocks = [..]
        "if % %", "unless % %", "for % in % %", "for % = % in % %", "repeat while % %"
        "repeat % times %", "repeat %", "repeat until % %", "for % in % to % by % %",
        "for % in % to % via % %", "for % in % to % %", "for % % in % %", "do %"
        "for % in recursive % %", "test %", "with % %", "result of %"
    for %n in %need_blocks:
        if (%tree.stub is %n):
            %bits = (((% upgraded) if (% is syntax tree) else %) for % in %tree)
            unless ((last in %bits) is "Block" syntax tree):
                %body = (last in %bits)
                %bits.(length of %bits) = (=lua "Block(\%body.source, \%body)")
            return (=lua "Action(\%tree.source, unpack(\%bits))")