1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package template
import (
"fmt"
"io"
"reflect"
"template/parse"
)
// Set holds a set of related templates that can refer to one another by name.
// The zero value represents an empty set.
// A template may be a member of multiple sets.
type Set struct {
tmpl map[string]*Template
leftDelim string
rightDelim string
parseFuncs FuncMap
execFuncs map[string]reflect.Value
}
func (s *Set) init() {
if s.tmpl == nil {
s.tmpl = make(map[string]*Template)
s.parseFuncs = make(FuncMap)
s.execFuncs = make(map[string]reflect.Value)
}
}
// Delims sets the action delimiters, to be used in a subsequent
// parse, to the specified strings.
// An empty delimiter stands for the corresponding default: {{ or }}.
// The return value is the set, so calls can be chained.
func (s *Set) Delims(left, right string) *Set {
s.leftDelim = left
s.rightDelim = right
return s
}
// Funcs adds the elements of the argument map to the set's function map. It
// panics if a value in the map is not a function with appropriate return
// type.
// The return value is the set, so calls can be chained.
func (s *Set) Funcs(funcMap FuncMap) *Set {
s.init()
addValueFuncs(s.execFuncs, funcMap)
addFuncs(s.parseFuncs, funcMap)
return s
}
// Add adds the argument templates to the set. It panics if two templates
// with the same name are added or if a template is already a member of
// a set.
// The return value is the set, so calls can be chained.
func (s *Set) Add(templates ...*Template) *Set {
for _, t := range templates {
if err := s.add(t); err != nil {
panic(err)
}
}
return s
}
// add adds the argument template to the set.
func (s *Set) add(t *Template) error {
s.init()
if t.set != nil {
return fmt.Errorf("template: %q already in a set", t.name)
}
if _, ok := s.tmpl[t.name]; ok {
return fmt.Errorf("template: %q already defined in set", t.name)
}
s.tmpl[t.name] = t
t.set = s
return nil
}
// Template returns the template with the given name in the set,
// or nil if there is no such template.
func (s *Set) Template(name string) *Template {
return s.tmpl[name]
}
// FuncMap returns the set's function map.
func (s *Set) FuncMap() FuncMap {
return s.parseFuncs
}
// Execute applies the named template to the specified data object, writing
// the output to wr.
func (s *Set) Execute(wr io.Writer, name string, data interface{}) error {
tmpl := s.tmpl[name]
if tmpl == nil {
return fmt.Errorf("template: no template %q in set", name)
}
return tmpl.Execute(wr, data)
}
// Parse parses a string into a set of named templates. Parse may be called
// multiple times for a given set, adding the templates defined in the string
// to the set. If a template is redefined, the element in the set is
// overwritten with the new definition.
func (s *Set) Parse(text string) (*Set, error) {
trees, err := parse.Set(text, s.leftDelim, s.rightDelim, s.parseFuncs, builtins)
if err != nil {
return nil, err
}
s.init()
for name, tree := range trees {
tmpl := New(name)
tmpl.Tree = tree
tmpl.addToSet(s)
s.tmpl[name] = tmpl
}
return s, nil
}
|
