From b11853c05013a6e635fb4903382e1f85576d9195 Mon Sep 17 00:00:00 2001
From: Vladimir Mihailenco <vladimir.webdev@gmail.com>
Date: Wed, 2 Jul 2014 16:18:19 +0300
Subject: [PATCH] Allow Pipelined funcs to return error.

---
 multi.go    | 6 ++++--
 pipeline.go | 6 ++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/multi.go b/multi.go
index e75fbc8a..bff38dfa 100644
--- a/multi.go
+++ b/multi.go
@@ -55,9 +55,11 @@ func (c *Multi) Discard() error {
 // Exec always returns list of commands. If transaction fails
 // TxFailedErr is returned. Otherwise Exec returns error of the first
 // failed command or nil.
-func (c *Multi) Exec(f func()) ([]Cmder, error) {
+func (c *Multi) Exec(f func() error) ([]Cmder, error) {
 	c.cmds = []Cmder{NewStatusCmd("MULTI")}
-	f()
+	if err := f(); err != nil {
+		return nil, err
+	}
 	c.cmds = append(c.cmds, NewSliceCmd("EXEC"))
 
 	cmds := c.cmds
diff --git a/pipeline.go b/pipeline.go
index 6d436d2d..1f51da45 100644
--- a/pipeline.go
+++ b/pipeline.go
@@ -20,9 +20,11 @@ func (c *Client) Pipeline() *Pipeline {
 	}
 }
 
-func (c *Client) Pipelined(f func(*Pipeline)) ([]Cmder, error) {
+func (c *Client) Pipelined(f func(*Pipeline) error) ([]Cmder, error) {
 	pc := c.Pipeline()
-	f(pc)
+	if err := f(pc); err != nil {
+		return nil, err
+	}
 	cmds, err := pc.Exec()
 	pc.Close()
 	return cmds, err