* Primop `__currentSystem' to return the current platform identifier.

This commit is contained in:
Eelco Dolstra 2005-04-10 17:38:19 +00:00
parent b4b51c9f93
commit c9c58dba55
2 changed files with 14 additions and 9 deletions

View file

@ -89,11 +89,5 @@ void checkVarDefs(const ATermMap & def, Expr e);
/* Create an expression representing a boolean. */
Expr makeBool(bool b);
/* Create an expression representing a string. */
Expr makeString(const string & s);
/* Create an expression representing a path. */
Expr makePath(const Path & path);
#endif /* !__NIXEXPR_H */

View file

@ -357,21 +357,21 @@ static Expr primFalse(EvalState & state, const ATermVector & args)
/* Return the null value. */
Expr primNull(EvalState & state, const ATermVector & args)
static Expr primNull(EvalState & state, const ATermVector & args)
{
return makeNull();
}
/* Determine whether the argument is the null value. */
Expr primIsNull(EvalState & state, const ATermVector & args)
static Expr primIsNull(EvalState & state, const ATermVector & args)
{
return makeBool(matchNull(evalExpr(state, args[0])));
}
/* Apply a function to every element of a list. */
Expr primMap(EvalState & state, const ATermVector & args)
static Expr primMap(EvalState & state, const ATermVector & args)
{
Expr fun = evalExpr(state, args[0]);
Expr list = evalExpr(state, args[1]);
@ -388,11 +388,22 @@ Expr primMap(EvalState & state, const ATermVector & args)
}
/* Return a string constant representing the current platform. Note!
that differs between platforms, so Nix expressions using
`__currentSystem' can evaluate to different values on different
platforms. */
static Expr primCurrentSystem(EvalState & state, const ATermVector & args)
{
return makeStr(toATerm(thisSystem));
}
void EvalState::addPrimOps()
{
addPrimOp("true", 0, primTrue);
addPrimOp("false", 0, primFalse);
addPrimOp("null", 0, primNull);
addPrimOp("__currentSystem", 0, primCurrentSystem);
addPrimOp("import", 1, primImport);
addPrimOp("derivation", 1, primDerivation);