Add isPath primop

this is added for completeness' sake since all the other possible
`builtins.typeOf` results have a corresponding `builtins.is<Type>`
This commit is contained in:
zimbatm 2018-01-29 12:36:59 +00:00
parent 56f1ed5579
commit 514b3c7f83
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GPG key ID: 71BAF6D40C1D63D7
3 changed files with 17 additions and 0 deletions

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@ -861,6 +861,14 @@ x: x + 456</programlisting>
</varlistentry>
<varlistentry><term><function>builtins.isPath</function>
<replaceable>e</replaceable></term>
<listitem><para>Return <literal>true</literal> if
<replaceable>e</replaceable> evaluates to a path, and
<literal>false</literal> otherwise.</para></listitem>
</varlistentry>
<varlistentry xml:id='builtin-isNull'>
<term><function>isNull</function>

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@ -315,6 +315,12 @@ static void prim_isBool(EvalState & state, const Pos & pos, Value * * args, Valu
mkBool(v, args[0]->type == tBool);
}
/* Determine whether the argument is a path. */
static void prim_isPath(EvalState & state, const Pos & pos, Value * * args, Value & v)
{
state.forceValue(*args[0]);
mkBool(v, args[0]->type == tPath);
}
struct CompareValues
{
@ -2169,6 +2175,7 @@ void EvalState::createBaseEnv()
addPrimOp("__isInt", 1, prim_isInt);
addPrimOp("__isFloat", 1, prim_isFloat);
addPrimOp("__isBool", 1, prim_isBool);
addPrimOp("__isPath", 1, prim_isPath);
addPrimOp("__genericClosure", 1, prim_genericClosure);
addPrimOp("abort", 1, prim_abort);
addPrimOp("__addErrorContext", 2, prim_addErrorContext);

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@ -20,6 +20,8 @@ with builtins;
(isFloat (1 - 2.0))
(isBool (true && false))
(isBool null)
(isPath /nix/store)
(isPath ./.)
(isAttrs { x = 123; })
(isAttrs null)
(typeOf (3 * 4))