civodul pushed a commit to tag 1.8
in repository guix.
commit 0cd6596b0e75870dc59f17848c6c152e2b2c6dba
Author: Eelco Dolstra <[email protected]>
Date: Mon Sep 22 16:03:55 2014 +0200
Add ‘deepSeq’ primop
Note that unlike ‘lib.deepSeq’ in Nixpkgs, this handles cycles.
---
src/libexpr/primops.cc | 11 +++++++++++
tests/lang/eval-fail-deepseq.nix | 1 +
tests/lang/eval-okay-deepseq.exp | 1 +
tests/lang/eval-okay-deepseq.nix | 1 +
4 files changed, 14 insertions(+), 0 deletions(-)
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 2da15b3..a25bd88 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -392,6 +392,16 @@ void prim_seq(EvalState & state, const Pos & pos, Value *
* args, Value & v)
}
+/* Evaluate the first argument deeply (i.e. recursing into lists and
+ attrsets), then return the second argument. */
+void prim_deepSeq(EvalState & state, const Pos & pos, Value * * args, Value &
v)
+{
+ state.forceValueDeep(*args[0]);
+ state.forceValue(*args[1]);
+ v = *args[1];
+}
+
+
/* Evaluate the first expression and print it on standard error. Then
return the second expression. Useful for debugging. */
static void prim_trace(EvalState & state, const Pos & pos, Value * * args,
Value & v)
@@ -1435,6 +1445,7 @@ void EvalState::createBaseEnv()
// Strictness
addPrimOp("__seq", 2, prim_seq);
+ addPrimOp("__deepSeq", 2, prim_deepSeq);
// Debugging
addPrimOp("__trace", 2, prim_trace);
diff --git a/tests/lang/eval-fail-deepseq.nix b/tests/lang/eval-fail-deepseq.nix
new file mode 100644
index 0000000..9baa49b
--- /dev/null
+++ b/tests/lang/eval-fail-deepseq.nix
@@ -0,0 +1 @@
+builtins.deepSeq { x = abort "foo"; } 456
diff --git a/tests/lang/eval-okay-deepseq.exp b/tests/lang/eval-okay-deepseq.exp
new file mode 100644
index 0000000..8d38505
--- /dev/null
+++ b/tests/lang/eval-okay-deepseq.exp
@@ -0,0 +1 @@
+456
diff --git a/tests/lang/eval-okay-deepseq.nix b/tests/lang/eval-okay-deepseq.nix
new file mode 100644
index 0000000..53aa4b1
--- /dev/null
+++ b/tests/lang/eval-okay-deepseq.nix
@@ -0,0 +1 @@
+builtins.deepSeq (let as = { x = 123; y = as; }; in as) 456
