Mercurial > genshi > mirror
annotate markup/builder.py @ 27:b4f78c05e5c9 trunk
* Fix the boilerplate in the Python source files.
* Some more docstrings and cosmetic fixes.
| author | cmlenz |
|---|---|
| date | Wed, 28 Jun 2006 09:28:09 +0000 |
| parents | cc92d74ce9e5 |
| children | 35956040ba6e |
| rev | line source |
|---|---|
| 1 | 1 # -*- coding: utf-8 -*- |
| 2 # | |
| 3 # Copyright (C) 2006 Christopher Lenz | |
| 4 # All rights reserved. | |
| 5 # | |
| 6 # This software is licensed as described in the file COPYING, which | |
| 7 # you should have received as part of this distribution. The terms | |
| 27 | 8 # are also available at http://markup.cmlenz.net/wiki/License. |
| 1 | 9 # |
| 10 # This software consists of voluntary contributions made by many | |
| 11 # individuals. For the exact contribution history, see the revision | |
| 27 | 12 # history and logs, available at http://markup.cmlenz.net/log/. |
| 1 | 13 |
|
19
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
|
14 from markup.core import Attributes, Namespace, QName, Stream |
| 1 | 15 |
| 16 __all__ = ['Fragment', 'Element', 'tag'] | |
| 17 | |
| 18 | |
| 19 class Fragment(object): | |
| 20 __slots__ = ['children'] | |
| 21 | |
| 22 def __init__(self): | |
| 23 self.children = [] | |
| 24 | |
| 25 def append(self, node): | |
| 26 """Append an element or string as child node.""" | |
| 27 if isinstance(node, (Element, basestring, int, float, long)): | |
| 28 # For objects of a known/primitive type, we avoid the check for | |
| 29 # whether it is iterable for better performance | |
| 30 self.children.append(node) | |
| 31 elif isinstance(node, Fragment): | |
| 32 self.children += node.children | |
| 33 elif node is not None: | |
| 34 try: | |
| 35 children = iter(node) | |
| 36 except TypeError: | |
| 37 self.children.append(node) | |
| 38 else: | |
| 39 for child in node: | |
| 40 self.append(children) | |
| 41 | |
| 42 def __add__(self, other): | |
| 43 return Fragment()(self, other) | |
| 44 | |
| 45 def __call__(self, *args): | |
| 46 for arg in args: | |
| 47 self.append(arg) | |
| 48 return self | |
| 49 | |
| 50 def generate(self): | |
| 51 """Generator that yield tags and text nodes as strings.""" | |
| 52 def _generate(): | |
| 53 for child in self.children: | |
| 54 if isinstance(child, Fragment): | |
| 55 for event in child.generate(): | |
| 56 yield event | |
| 57 else: | |
|
17
74cc70129d04
Refactoring to address #6: all match templates are now processed by a single filter, which means that match templates added by included templates are properly applied. A side effect of this refactoring is that `Context` objects may not be reused across multiple template processing runs.
cmlenz
parents:
1
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changeset
|
58 yield Stream.TEXT, unicode(child), (-1, -1) |
| 1 | 59 return Stream(_generate()) |
| 60 | |
| 61 def __iter__(self): | |
| 62 return iter(self.generate()) | |
| 63 | |
| 64 def __str__(self): | |
| 65 return str(self.generate()) | |
| 66 | |
| 67 def __unicode__(self): | |
| 68 return unicode(self.generate()) | |
| 69 | |
| 70 | |
| 71 class Element(Fragment): | |
| 72 """Simple XML output generator based on the builder pattern. | |
| 73 | |
| 74 Construct XML elements by passing the tag name to the constructor: | |
| 75 | |
| 76 >>> print Element('strong') | |
| 77 <strong/> | |
| 78 | |
| 79 Attributes can be specified using keyword arguments. The values of the | |
| 80 arguments will be converted to strings and any special XML characters | |
| 81 escaped: | |
| 82 | |
| 83 >>> print Element('textarea', rows=10, cols=60) | |
| 84 <textarea rows="10" cols="60"/> | |
| 85 >>> print Element('span', title='1 < 2') | |
| 86 <span title="1 < 2"/> | |
| 87 >>> print Element('span', title='"baz"') | |
| 88 <span title=""baz""/> | |
| 89 | |
| 90 The " character is escaped using a numerical entity. | |
| 91 The order in which attributes are rendered is undefined. | |
| 92 | |
| 93 If an attribute value evaluates to `None`, that attribute is not included | |
| 94 in the output: | |
| 95 | |
| 96 >>> print Element('a', name=None) | |
| 97 <a/> | |
| 98 | |
| 99 Attribute names that conflict with Python keywords can be specified by | |
| 100 appending an underscore: | |
| 101 | |
| 102 >>> print Element('div', class_='warning') | |
| 103 <div class="warning"/> | |
| 104 | |
| 105 Nested elements can be added to an element using item access notation. | |
| 106 The call notation can also be used for this and for adding attributes | |
| 107 using keyword arguments, as one would do in the constructor. | |
| 108 | |
| 109 >>> print Element('ul')(Element('li'), Element('li')) | |
| 110 <ul><li/><li/></ul> | |
| 111 >>> print Element('a')('Label') | |
| 112 <a>Label</a> | |
| 113 >>> print Element('a')('Label', href="target") | |
| 114 <a href="target">Label</a> | |
| 115 | |
| 116 Text nodes can be nested in an element by adding strings instead of | |
| 117 elements. Any special characters in the strings are escaped automatically: | |
| 118 | |
| 119 >>> print Element('em')('Hello world') | |
| 120 <em>Hello world</em> | |
| 121 >>> print Element('em')(42) | |
| 122 <em>42</em> | |
| 123 >>> print Element('em')('1 < 2') | |
| 124 <em>1 < 2</em> | |
| 125 | |
| 126 This technique also allows mixed content: | |
| 127 | |
| 128 >>> print Element('p')('Hello ', Element('b')('world')) | |
| 129 <p>Hello <b>world</b></p> | |
| 130 | |
| 131 Elements can also be combined with other elements or strings using the | |
| 132 addition operator, which results in a `Fragment` object that contains the | |
| 133 operands: | |
| 134 | |
| 135 >>> print Element('br') + 'some text' + Element('br') | |
| 136 <br/>some text<br/> | |
| 137 | |
| 138 Elements with a namespace can be generated using the `Namespace` and/or | |
| 139 `QName` classes: | |
| 140 | |
| 141 >>> from markup.core import Namespace | |
| 142 >>> xhtml = Namespace('http://www.w3.org/1999/xhtml') | |
| 143 >>> print Element(xhtml.html, lang='en') | |
| 144 <html lang="en" xmlns="http://www.w3.org/1999/xhtml"/> | |
| 145 """ | |
| 146 __slots__ = ['tag', 'attrib'] | |
| 147 | |
| 148 def __init__(self, tag_, **attrib): | |
| 149 Fragment.__init__(self) | |
| 150 self.tag = QName(tag_) | |
| 151 self.attrib = Attributes() | |
| 152 self(**attrib) | |
| 153 | |
| 154 def __call__(self, *args, **kwargs): | |
| 155 for attr, value in kwargs.items(): | |
| 156 if value is None: | |
| 157 continue | |
| 158 attr = attr.rstrip('_').replace('_', '-') | |
| 159 self.attrib.set(attr, value) | |
| 160 return Fragment.__call__(self, *args) | |
| 161 | |
| 162 def generate(self): | |
| 163 """Generator that yield tags and text nodes as strings.""" | |
| 164 def _generate(): | |
| 165 yield Stream.START, (self.tag, self.attrib), (-1, -1) | |
| 166 for kind, data, pos in Fragment.generate(self): | |
| 167 yield kind, data, pos | |
| 168 yield Stream.END, self.tag, (-1, -1) | |
| 169 return Stream(_generate()) | |
| 170 | |
| 171 | |
| 172 class ElementFactory(object): | |
| 173 | |
|
19
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
|
174 def __init__(self, namespace=None): |
| 20 | 175 if namespace and not isinstance(namespace, Namespace): |
|
19
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
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176 namespace = Namespace(namespace) |
|
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
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177 self.namespace = namespace |
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704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
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178 |
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704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
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changeset
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179 def __getitem__(self, namespace): |
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704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
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changeset
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180 return ElementFactory(namespace) |
|
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
|
181 |
|
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
|
182 def __getattr__(self, name): |
|
704f10b06507
Enable `ElementFactory` to create namespaced elements.
cmlenz
parents:
17
diff
changeset
|
183 return Element(self.namespace and self.namespace[name] or name) |
| 1 | 184 |
| 185 | |
| 186 tag = ElementFactory() |