From 08ec19535d9394afdaad279d28181cee7e4c3a51 Mon Sep 17 00:00:00 2001
From: Sangbum Kim <sangbumkim@amuz.es>
Date: Fri, 13 Jul 2018 01:29:26 +0900
Subject: [PATCH] =?UTF-8?q?template=20=ED=95=A8=EC=88=98=20=EC=B6=94?=
 =?UTF-8?q?=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 tmpl/internal.go | 23 +++++++++++++++++
 tmpl/map.go      | 66 ++++++++++++++++++++++++++++++++++++++++++++++++
 tmpl/stub.s      |  1 +
 3 files changed, 90 insertions(+)
 create mode 100644 tmpl/internal.go
 create mode 100644 tmpl/map.go
 create mode 100644 tmpl/stub.s

diff --git a/tmpl/internal.go b/tmpl/internal.go
new file mode 100644
index 0000000..3112d40
--- /dev/null
+++ b/tmpl/internal.go
@@ -0,0 +1,23 @@
+package tmpl
+
+import (
+	"reflect"
+	_ "unsafe"
+)
+
+//go:linkname indirectInterface text/template.indirectInterface
+//go:nosplit
+func indirectInterface(v reflect.Value) reflect.Value
+
+//go:linkname truth text/template.truth
+//go:nosplit
+func truth(arg reflect.Value) bool
+
+//go:linkname isTrue text/template.isTrue
+//go:nosplit
+func isTrue(arg reflect.Value) (truth, ok bool)
+
+func evalTrue(val reflect.Value) (truth bool) {
+	truth, _ = isTrue(val)
+	return
+}
diff --git a/tmpl/map.go b/tmpl/map.go
new file mode 100644
index 0000000..9bbdce5
--- /dev/null
+++ b/tmpl/map.go
@@ -0,0 +1,66 @@
+package tmpl
+
+import (
+	"reflect"
+	_ "unsafe"
+)
+
+type TmplMap struct {
+	reflect.Value
+}
+
+func (m TmplMap) Keys() ([]reflect.Value) {
+	return m.MapKeys()
+}
+
+func (m TmplMap) MapWithDefaults(arg0 reflect.Value, args ...reflect.Value) (v reflect.Value) {
+	if iarg0 := indirectInterface(arg0); evalTrue(iarg0) {
+		if v = m.MapIndex(iarg0); evalTrue(v) {
+			return
+		}
+	}
+
+	for _, v = range args {
+		if truth(v) {
+			break
+		}
+	}
+	return
+}
+
+func (m TmplMap) Map(arg0 reflect.Value, args ...reflect.Value) (v reflect.Value) {
+	if iarg0 := indirectInterface(arg0); evalTrue(iarg0) {
+		if v = m.MapIndex(iarg0); evalTrue(v) {
+			return
+		}
+	}
+	argLen := len(args)
+	if argLen == 0 {
+		return
+	}
+	keys, defaultValue := args[:argLen-1], args[argLen-1]
+	for _, k := range keys {
+		if ik := indirectInterface(k); !evalTrue(ik) {
+		} else if v = m.Value.MapIndex(ik); evalTrue(v) {
+			return
+		}
+	}
+	v = defaultValue
+	return
+}
+
+func MakeMapFunc(arg ...reflect.Value) TmplMap {
+	if len(arg)%2 != 0 {
+		panic("bad makemap")
+	}
+
+	m := reflect.MakeMapWithSize(reflect.TypeOf(map[interface{}]interface{}{}), len(arg)/2)
+	for i := 0; i < len(arg); i += 2 {
+		k, v := indirectInterface(arg[i]), indirectInterface(arg[i+1])
+		if !(evalTrue(k) && evalTrue(v)) {
+			continue
+		}
+		m.SetMapIndex(k, v)
+	}
+	return TmplMap{m}
+}
diff --git a/tmpl/stub.s b/tmpl/stub.s
new file mode 100644
index 0000000..34f84cf
--- /dev/null
+++ b/tmpl/stub.s
@@ -0,0 +1 @@
+// make compiler happy
\ No newline at end of file