be06fc096a
better path going forward to handling upgrades. Old syntax files will stick around for compatibility purposes. Old syntax can be parsed into valid syntax trees via the old syntax (.peg) files, and then old syntax trees should be valid and can be upgraded via the normal code path. This change has lots of improvements to Nomsu codegen too.
57 lines
1.9 KiB
Plaintext
57 lines
1.9 KiB
Plaintext
-- This file contains the datastructures used to represent parsed Nomsu syntax trees,
|
|
-- as well as the logic for converting them to Lua code.
|
|
{:repr} = require 'utils'
|
|
{:insert, :remove, :concat} = table
|
|
{:Source} = require "code_obj"
|
|
unpack or= table.unpack
|
|
|
|
AST = {}
|
|
AST.is_syntax_tree = (n, t=nil)->
|
|
type(n) == 'table' and getmetatable(n) and AST[n.type] == getmetatable(n) and (t == nil or n.type == t)
|
|
|
|
types = {"Number", "Var", "Block", "EscapedNomsu", "Text", "List", "Dict", "DictEntry",
|
|
"IndexChain", "Action", "FileChunks"}
|
|
for name in *types
|
|
cls = {}
|
|
with cls
|
|
.__class = cls
|
|
.__index = cls
|
|
.__name = name
|
|
.type = name
|
|
.is_instance = (x)=> getmetatable(x) == @
|
|
.__tostring = => "#{@type}(#{repr tostring(@source)}, #{concat([repr(v) for v in *@], ', ')})"
|
|
.map = (fn)=>
|
|
replacement = fn(@)
|
|
if replacement != nil then return replacement or nil
|
|
replacements = {}
|
|
changes = false
|
|
for i,v in ipairs(@)
|
|
replacement = if AST.is_syntax_tree(v)
|
|
v\map(fn)
|
|
else v
|
|
changes or= replacement != v
|
|
replacements[#replacements+1] = replacement
|
|
return @ unless changes
|
|
return (@__class)(@source, unpack(replacements))
|
|
|
|
AST[name] = setmetatable cls,
|
|
__tostring: => @name
|
|
__call: (source, ...)=>
|
|
if type(source) == 'string'
|
|
source = Source\from_string(source)
|
|
for i=1,select('#', ...) do assert(select(i,...))
|
|
assert(Source\is_instance(source))
|
|
inst = {:source, ...}
|
|
setmetatable(inst, @)
|
|
if inst.__init then inst\__init!
|
|
return inst
|
|
|
|
AST.Action.__init = =>
|
|
stub_bits = [type(a) == 'string' and a or '%' for a in *@]
|
|
@stub = concat stub_bits, " "
|
|
|
|
AST.Action.get_args = =>
|
|
[tok for tok in *@ when type(tok) != 'string']
|
|
|
|
return AST
|