from typing import * import textwrap import re import copy import json from collections import defaultdict from re import Pattern from agast import * global i i = 0 class GenResult: def __init__(self, pd: str = "", ex: str = ""): self.literals: Dict[str, str] = dict() self.parse_rules: defaultdict[str, List[str]] = defaultdict(list) self.starts: Set[str] = set() self.extra = ex self.trans: List[str] = list() @property def transdef(self) -> str: s = self.trans if not s: s = ["pass"] return "\n" + "\n".join(map(lambda c: f" {c}", s)) @property def parser_data(self) -> str: s = [] for sym, pat in self.literals.items(): s.append(f"{sym}: {pat}") for name, rules in self.parse_rules.items(): srules = " | ".join(rules) s.append(f"{name}: {srules}") s.append("%import common.WS") s.append("%ignore WS") return "\n".join(s) def gen(program: List[Decl]) -> GenResult: res = GenResult() def gen(prefix: str = "", suffix: str = "") -> str: global i presan = re.sub("[^0-9a-zA-Z]+", "_", prefix) sufsan = re.sub("[^0-9a-zA-Z]+", "_", suffix) i += 1 return f"{presan}{i}{sufsan}" def v(name: str) -> str: return f"__ag_{name}" # builtins builtins: Dict[str, str] = { "parseInt": "", } # collect a list of name -> iface declarations ifaces: Dict[str, Iface] = dict( map( lambda c: (c.name, cast(Iface, c)), filter(lambda c: isinstance(c, Iface), program), ) ) # list of node -> iface mappings what_ifaces: Dict[str, Set[str]] = dict() what_fields: Dict[str, Dict[str, str]] = dict() for node in filter(lambda c: isinstance(c, Node), program): node = cast(Node, node) # all_fields = dict() what_ifaces[node.name] = set(node.ifaces) this_fields = dict() for iface in node.ifaces: fields = ifaces[iface].fields for field in fields: if field.name in this_fields: raise Exception("duplicate field name") this_fields[field.name] = field.ty what_fields[node.name] = this_fields print("what_ifaces:", what_ifaces) print("what_fields:", what_fields) # a high-level dictionary of productions; this has sub-productions # that should be further expanded at a later step before converting # into lark code productions_hi: Dict[str, Union[str, List[str]]] = dict() # TODO: this should probably not be inlined here, but i'll move it # out once i get more info into the 'env' def collect_required_thunks( env: List[Tuple[str, NodeRef]], expr: Expr ) -> Dict[str, str]: names = dict(env) print(f"collect_required_thunks({expr})", expr.__class__) if isinstance(expr, ExprDot): return collect_required_thunks(env, expr.left) elif isinstance(expr, ExprMul): a = collect_required_thunks(env, expr.left) b = collect_required_thunks(env, expr.right) a.update(b) return a elif isinstance(expr, ExprAdd): a = collect_required_thunks(env, expr.left) b = collect_required_thunks(env, expr.right) a.update(b) return a elif isinstance(expr, ExprCall): return collect_required_thunks(env, expr.func) elif isinstance(expr, ExprName): if expr.name not in names and expr.name not in builtins: raise Exception(f"unbound name '{expr.name}'") return dict() raise Exception(f"unhandled {expr.__class__}") node_map = dict( map(lambda n: (n.name, n), filter(lambda c: isinstance(c, Node), program)) ) node_name_map = dict( map(lambda n: (n[0], gen(n[1].name.lower())), node_map.items()) ) for node in node_map.values(): node = cast(Node, node) node_name_lower = node.name.lower() node_name = node_name_map[node.name] res.parse_rules[f"?{node_name_lower}"].append(node_name) res.starts.add(node_name_lower) class_decl = textwrap.dedent( f""" class {v(node_name)}: pass """ ) res.extra += class_decl print(node.name, node.ifaces) for variant in node.variants: v_class_name = gen(f"{node_name}_var") class_decl = textwrap.dedent( f""" class {v(v_class_name)}({v(node_name)}): ''' ''' pass """ ) res.extra += class_decl prod_name = gen(node_name + "_") res.parse_rules[node_name].append(prod_name) print("PRODUCTION", prod_name, variant.prod) # resolving a production just means checking to make sure it's a # type that exists or it's a regex def resolve_production(sym: Sym) -> str: print(f"resolve_production({sym})") if isinstance(sym, SymRename): if isinstance(sym.ty, NodeRefByName): if sym.ty.name in node_name_map: return node_name_map[sym.ty.name] else: raise Exception( f"unresolved name {sym.ty.name} in production" ) elif isinstance(sym.ty, NodeRegex): sym_name = gen("sym") res.literals[sym_name] = f"/{sym.ty.pat.pattern}/" return sym_name elif isinstance(sym, SymLit): sym_name = gen("lit") # hack to make repr have double quotes res.literals[sym_name] = json.dumps(sym.lit) return sym_name raise Exception(f"unhandled {sym.__class__}") seq = [] for sym in variant.prod: n = resolve_production(sym) seq.append(n) res.parse_rules[prod_name].append(" ".join(seq)) # create an environment for checking the equations based on # the production env: List[Tuple[str, NodeRef]] = list() for sym in variant.prod: if isinstance(sym, SymRename): env.append((sym.name, sym.ty)) print(env) # for each of the equations, find out what the equation is # trying to compute, and generate a thunk corresponding to # that value. for eq in variant.equations: eq_name = gen(f"eq_{node.name}") thunk_name = gen(f"thunk_{node.name}") print("RHS", eq.rhs, eq.rhs.id) collect_required_thunks(copy.deepcopy(env), eq.rhs) func_impl = textwrap.dedent( f""" def {eq_name}() -> None: ''' {repr(eq)} ''' pass def {thunk_name}() -> Thunk[None]: return Thunk({eq_name}) """ ) print(f"```py\n{func_impl}\n```") res.extra += func_impl # this is a "type alias" that connects it to one of the generated # names above res.extra += f"{node.name} = {v(node_name)}" return res