wroclaw-git-backups/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2025-06-26 15:51:15 +02:00
Code Activity

* Use a symbol table to represent identifiers and attribute names

Browse source 
efficiently.  The symbol table ensures that there is only one copy
  of each symbol, thus allowing symbols to be compared efficiently
  using a pointer equality test.
This commit is contained in:
Eelco Dolstra 2010-04-13 12:25:42 +00:00
parent 10e8b1fd15
commit ac1e8f40d4
15 changed files with 228 additions and 101 deletions
Download patch file Download diff file Expand all files Collapse all files

45
src/libexpr/eval.cc
View file

@ -43,8 +43,8 @@ std::ostream & operator << (std::ostream & str, Value & v)
break;
case tAttrs:
str << "{ ";
foreach (Bindings::iterator, i, *v.attrs)
str << i->first << " = " << i->second << "; ";
foreach (Bindings::iterator, i, *v.attrs)
str << (string) i->first << " = " << i->second << "; ";
str << "}";
break;
case tList:
@ -91,7 +91,14 @@ string showType(Value & v)
}
EvalState::EvalState() : baseEnv(allocEnv())
EvalState::EvalState()
: sWith(symbols.create("<with>"))
, sOutPath(symbols.create("outPath"))
, sDrvPath(symbols.create("drvPath"))
, sType(symbols.create("type"))
, sMeta(symbols.create("meta"))
, sName(symbols.create("name"))
, baseEnv(allocEnv())
{
nrValues = nrEnvs = nrEvaluated = recursionDepth = maxRecursionDepth = 0;
deepestStack = (char *) -1;
@ -110,9 +117,9 @@ EvalState::~EvalState()
void EvalState::addConstant(const string & name, Value & v)
{
baseEnv.bindings[name] = v;
baseEnv.bindings[symbols.create(name)] = v;
string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name;
(*baseEnv.bindings["builtins"].attrs)[name2] = v;
(*baseEnv.bindings[symbols.create("builtins")].attrs)[symbols.create(name2)] = v;
nrValues += 2;
}
@ -124,9 +131,9 @@ void EvalState::addPrimOp(const string & name,
v.type = tPrimOp;
v.primOp.arity = arity;
v.primOp.fun = primOp;
baseEnv.bindings[name] = v;
baseEnv.bindings[symbols.create(name)] = v;
string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name;
(*baseEnv.bindings["builtins"].attrs)[name2] = v;
(*baseEnv.bindings[symbols.create("builtins")].attrs)[symbols.create(name2)] = v;
nrValues += 2;
}
@ -225,12 +232,12 @@ void mkPath(Value & v, const char * s)
}
static Value * lookupWith(Env * env, const Sym & name)
Value * EvalState::lookupWith(Env * env, const Symbol & name)
{
if (!env) return 0;
Value * v = lookupWith(env->up, name);
if (v) return v;
Bindings::iterator i = env->bindings.find("<with>");
Bindings::iterator i = env->bindings.find(sWith);
if (i == env->bindings.end()) return 0;
Bindings::iterator j = i->second.attrs->find(name);
if (j != i->second.attrs->end()) return &j->second;
@ -238,7 +245,7 @@ static Value * lookupWith(Env * env, const Sym & name)
}
static Value * lookupVar(Env * env, const Sym & name)
Value * EvalState::lookupVar(Env * env, const Symbol & name)
{
/* First look for a regular variable binding for `name'. */
for (Env * env2 = env; env2; env2 = env2->up) {
@ -318,7 +325,7 @@ void EvalState::evalFile(const Path & path, Value & v)
Expr * e = parseTrees[path];
if (!e) {
e = parseExprFromFile(path);
e = parseExprFromFile(*this, path);
parseTrees[path] = e;
}
@ -428,9 +435,9 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v)
/* The inherited attributes, on the other hand, are
evaluated in the original environment. */
foreach (list<string>::iterator, i, inherited) {
foreach (list<Symbol>::iterator, i, inherited) {
Value & v2 = env2.bindings[*i];
mkCopy(v2, *lookupVar(&env, *i));
mkCopy(v2, *state.lookupVar(&env, *i));
}
}
@ -441,9 +448,9 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v)
mkThunk(v2, env, i->second);
}
foreach (list<string>::iterator, i, inherited) {
foreach (list<Symbol>::iterator, i, inherited) {
Value & v2 = (*v.attrs)[*i];
mkCopy(v2, *lookupVar(&env, *i));
mkCopy(v2, *state.lookupVar(&env, *i));
}
}
}
@ -459,7 +466,7 @@ void ExprList::eval(EvalState & state, Env & env, Value & v)
void ExprVar::eval(EvalState & state, Env & env, Value & v)
{
Value * v2 = lookupVar(&env, name);
Value * v2 = state.lookupVar(&env, name);
state.forceValue(*v2);
v = *v2;
}
@ -631,7 +638,7 @@ void ExprWith::eval(EvalState & state, Env & env, Value & v)
Env & env2(state.allocEnv());
env2.up = &env;
Value & vAttrs = env2.bindings["<with>"];
Value & vAttrs = env2.bindings[state.sWith];
state.eval(env, attrs, vAttrs);
state.forceAttrs(vAttrs);
@ -871,7 +878,7 @@ string EvalState::forceStringNoCtx(Value & v)
bool EvalState::isDerivation(Value & v)
{
if (v.type != tAttrs) return false;
Bindings::iterator i = v.attrs->find("type");
Bindings::iterator i = v.attrs->find(sType);
return i != v.attrs->end() && forceStringNoCtx(i->second) == "derivation";
}
@ -915,7 +922,7 @@ string EvalState::coerceToString(Value & v, PathSet & context,
}
if (v.type == tAttrs) {
Bindings::iterator i = v.attrs->find("outPath");
Bindings::iterator i = v.attrs->find(sOutPath);
if (i == v.attrs->end())
throwTypeError("cannot coerce an attribute set (except a derivation) to a string");
return coerceToString(i->second, context, coerceMore, copyToStore);