From 3e5a019a070cbaac7d1248e208c66da9fdb23313 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Sun, 16 Nov 2003 17:46:31 +0000 Subject: * Some utility functions for working with ATerms. --- src/fix-ng/eval.cc | 108 ++++++++++++++++++++++++++++------------------------- 1 file changed, 57 insertions(+), 51 deletions(-) (limited to 'src/fix-ng/eval.cc') diff --git a/src/fix-ng/eval.cc b/src/fix-ng/eval.cc index 2b45b47984e8..55cb5fbcff27 100644 --- a/src/fix-ng/eval.cc +++ b/src/fix-ng/eval.cc @@ -16,6 +16,7 @@ EvalState::EvalState() /* Substitute an argument set into the body of a function. */ static Expr substArgs(Expr body, ATermList formals, Expr arg) { + ATMatcher m; ATermMap subs; Expr undefined = ATmake("Undefined"); @@ -23,9 +24,9 @@ static Expr substArgs(Expr body, ATermList formals, Expr arg) while (!ATisEmpty(formals)) { ATerm t = ATgetFirst(formals); Expr name, def; - if (ATmatch(t, "NoDefFormal()", &name)) + if (atMatch(m, t) >> "NoDefFormal" >> name) subs.set(name, undefined); - else if (ATmatch(t, "DefFormal(, )", &name, &def)) + else if (atMatch(m, t) >> "DefFormal" >> name >> def) subs.set(name, def); else abort(); /* can't happen */ formals = ATgetNext(formals); @@ -67,15 +68,17 @@ static Expr substArgs(Expr body, ATermList formals, Expr arg) (e.x) (e.y), y = e.x}'. */ ATerm expandRec(ATerm e, ATermList bnds) { + ATMatcher m; + /* Create the substitution list. */ ATermMap subs; ATermList bs = bnds; while (!ATisEmpty(bs)) { - char * s; + string s; Expr e2; - if (!ATmatch(ATgetFirst(bs), "Bind(, )", &s, &e2)) + if (!(atMatch(m, ATgetFirst(bs)) >> "Bind" >> s >> e2)) abort(); /* can't happen */ - subs.set(s, ATmake("Select(, )", e, s)); + subs.set(s, ATmake("Select(, )", e, s.c_str())); bs = ATgetNext(bs); } @@ -83,9 +86,9 @@ ATerm expandRec(ATerm e, ATermList bnds) ATermMap as; bs = bnds; while (!ATisEmpty(bs)) { - char * s; + string s; Expr e2; - if (!ATmatch(ATgetFirst(bs), "Bind(, )", &s, &e2)) + if (!(atMatch(m, ATgetFirst(bs)) >> "Bind" >> s >> e2)) abort(); /* can't happen */ as.set(s, substitute(subs, e2)); bs = ATgetNext(bs); @@ -98,8 +101,9 @@ ATerm expandRec(ATerm e, ATermList bnds) string evalString(EvalState & state, Expr e) { e = evalExpr(state, e); - char * s; - if (!ATmatch(e, "Str()", &s)) + ATMatcher m; + string s; + if (!(atMatch(m, e) >> "Str" >> s)) throw badTerm("string expected", e); return s; } @@ -108,8 +112,9 @@ string evalString(EvalState & state, Expr e) Path evalPath(EvalState & state, Expr e) { e = evalExpr(state, e); - char * s; - if (!ATmatch(e, "Path()", &s)) + ATMatcher m; + string s; + if (!(atMatch(m, e) >> "Path" >> s)) throw badTerm("path expected", e); return s; } @@ -118,78 +123,79 @@ Path evalPath(EvalState & state, Expr e) bool evalBool(EvalState & state, Expr e) { e = evalExpr(state, e); - if (ATmatch(e, "Bool(True)")) return true; - else if (ATmatch(e, "Bool(False)")) return false; + ATMatcher m; + if (atMatch(m, e) >> "Bool" >> "True") return true; + else if (atMatch(m, e) >> "Bool" >> "False") return false; else throw badTerm("expecting a boolean", e); } Expr evalExpr2(EvalState & state, Expr e) { + ATMatcher m; Expr e1, e2, e3, e4; - char * s1; + string s1; /* Normal forms. */ - if (ATmatch(e, "Str()", &s1) || - ATmatch(e, "Path()", &s1) || - ATmatch(e, "Uri()", &s1) || - ATmatch(e, "Bool()", &e1) || - ATmatch(e, "Function([], )", &e1, &e2) || - ATmatch(e, "Attrs([])", &e1) || - ATmatch(e, "List([])", &e1)) + if (atMatch(m, e) >> "Str" || + atMatch(m, e) >> "Path" || + atMatch(m, e) >> "Uri" || + atMatch(m, e) >> "Bool" || + atMatch(m, e) >> "Function" || + atMatch(m, e) >> "Attrs" || + atMatch(m, e) >> "List") return e; /* Any encountered variables must be undeclared or primops. */ - if (ATmatch(e, "Var()", &s1)) { - if ((string) s1 == "null") return primNull(state); + if (atMatch(m, e) >> "Var" >> s1) { + if (s1 == "null") return primNull(state); return e; } /* Function application. */ - if (ATmatch(e, "Call(, )", &e1, &e2)) { + if (atMatch(m, e) >> "Call" >> e1 >> e2) { + + ATermList formals; /* Evaluate the left-hand side. */ e1 = evalExpr(state, e1); /* Is it a primop or a function? */ - if (ATmatch(e1, "Var()", &s1)) { - string primop(s1); - if (primop == "import") return primImport(state, e2); - if (primop == "derivation") return primDerivation(state, e2); - if (primop == "toString") return primToString(state, e2); - if (primop == "baseNameOf") return primBaseNameOf(state, e2); - if (primop == "isNull") return primIsNull(state, e2); + if (atMatch(m, e1) >> "Var" >> s1) { + if (s1 == "import") return primImport(state, e2); + if (s1 == "derivation") return primDerivation(state, e2); + if (s1 == "toString") return primToString(state, e2); + if (s1 == "baseNameOf") return primBaseNameOf(state, e2); + if (s1 == "isNull") return primIsNull(state, e2); else throw badTerm("undefined variable/primop", e1); } - else if (ATmatch(e1, "Function([], )", &e3, &e4)) { + else if (atMatch(m, e1) >> "Function" >> formals >> e4) return evalExpr(state, - substArgs(e4, (ATermList) e3, evalExpr(state, e2))); - } + substArgs(e4, formals, evalExpr(state, e2))); else throw badTerm("expecting a function or primop", e1); } /* Attribute selection. */ - if (ATmatch(e, "Select(, )", &e1, &s1)) { - string name(s1); - Expr a = queryAttr(evalExpr(state, e1), name); - if (!a) throw badTerm(format("missing attribute `%1%'") % name, e); + if (atMatch(m, e) >> "Select" >> e1 >> s1) { + Expr a = queryAttr(evalExpr(state, e1), s1); + if (!a) throw badTerm(format("missing attribute `%1%'") % s1, e); return evalExpr(state, a); } /* Mutually recursive sets. */ ATermList bnds; - if (ATmatch(e, "Rec([])", &bnds)) - return expandRec(e, (ATermList) bnds); + if (atMatch(m, e) >> "Rec" >> bnds) + return expandRec(e, bnds); /* Let expressions `let {..., body = ...}' are just desugared into `(rec {..., body = ...}).body'. */ - if (ATmatch(e, "LetRec()", &e1)) - return evalExpr(state, ATmake("Select(Rec(), \"body\")", e1)); + if (atMatch(m, e) >> "LetRec" >> bnds) + return evalExpr(state, ATmake("Select(Rec(), \"body\")", bnds)); /* Conditionals. */ - if (ATmatch(e, "If(, , )", &e1, &e2, &e3)) { + if (atMatch(m, e) >> "If" >> e1 >> e2 >> e3) { if (evalBool(state, e1)) return evalExpr(state, e2); else @@ -197,33 +203,33 @@ Expr evalExpr2(EvalState & state, Expr e) } /* Assertions. */ - if (ATmatch(e, "Assert(, )", &e1, &e2)) { + if (atMatch(m, e) >> "Assert" >> e1 >> e2) { if (!evalBool(state, e1)) throw badTerm("guard failed", e); return evalExpr(state, e2); } /* Generic equality. */ - if (ATmatch(e, "OpEq(, )", &e1, &e2)) + if (atMatch(m, e) >> "OpEq" >> e1 >> e2) return makeBool(evalExpr(state, e1) == evalExpr(state, e2)); /* Generic inequality. */ - if (ATmatch(e, "OpNEq(, )", &e1, &e2)) + if (atMatch(m, e) >> "OpNEq" >> e1 >> e2) return makeBool(evalExpr(state, e1) != evalExpr(state, e2)); /* Negation. */ - if (ATmatch(e, "OpNot()", &e1)) + if (atMatch(m, e) >> "OpNot" >> e1) return makeBool(!evalBool(state, e1)); /* Implication. */ - if (ATmatch(e, "OpImpl(, )", &e1, &e2)) + if (atMatch(m, e) >> "OpImpl" >> e1 >> e2) return makeBool(!evalBool(state, e1) || evalBool(state, e2)); /* Conjunction (logical AND). */ - if (ATmatch(e, "OpAnd(, )", &e1, &e2)) + if (atMatch(m, e) >> "OpAnd" >> e1 >> e2) return makeBool(evalBool(state, e1) && evalBool(state, e2)); /* Disjunction (logical OR). */ - if (ATmatch(e, "OpOr(, )", &e1, &e2)) + if (atMatch(m, e) >> "OpOr" >> e1 >> e2) return makeBool(evalBool(state, e1) || evalBool(state, e2)); /* Barf. */ @@ -234,7 +240,7 @@ Expr evalExpr2(EvalState & state, Expr e) Expr evalExpr(EvalState & state, Expr e) { startNest(nest, lvlVomit, - format("evaluating expression: %1%") % printTerm(e)); + format("evaluating expression: %1%") % e); state.nrEvaluated++; -- cgit 1.4.1