wroclaw-git-backups/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2025-06-27 00:11:17 +02:00
Code Activity

* Implemented `map'.

Browse source
This commit is contained in:
Eelco Dolstra 2010-03-30 13:47:59 +00:00
parent d78a05ab40
commit 5b72d8a749
4 changed files with 139 additions and 108 deletions
Download patch file Download diff file Expand all files Collapse all files

22
src/libexpr/primops.cc
View file

@ -913,22 +913,28 @@ static Expr prim_tail(EvalState & state, const ATermVector & args)
throw Error("`tail' called on an empty list");
return makeList(ATgetNext(list));
}
#endif
/* Apply a function to every element of a list. */
static Expr prim_map(EvalState & state, const ATermVector & args)
static void prim_map(EvalState & state, Value * * args, Value & v)
{
Expr fun = evalExpr(state, args[0]);
ATermList list = evalList(state, args[1]);
state.forceFunction(*args[0]);
state.forceList(*args[1]);
ATermList res = ATempty;
for (ATermIterator i(list); i; ++i)
res = ATinsert(res, makeCall(fun, *i));
v.type = tList;
v.list.length = args[1]->list.length;
v.list.elems = state.allocValues(v.list.length);
return makeList(ATreverse(res));
for (unsigned int n = 0; n < v.list.length; ++n) {
v.list.elems[n].type = tApp;
v.list.elems[n].app.left = args[0];
v.list.elems[n].app.right = &args[1]->list.elems[n];
}
}
#if 0
/* Return the length of a list. This is an O(1) time operation. */
static Expr prim_length(EvalState & state, const ATermVector & args)
{
@ -1189,7 +1195,9 @@ void EvalState::createBaseEnv()
addPrimOp("__head", 1, prim_head);
#if 0
addPrimOp("__tail", 1, prim_tail);
#endif
addPrimOp("map", 2, prim_map);
#if 0
addPrimOp("__length", 1, prim_length);
#endif