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diff --git a/framework/src/ant/apache-ant-1.9.6/manual/Tasks/local.html b/framework/src/ant/apache-ant-1.9.6/manual/Tasks/local.html deleted file mode 100644 index c7ed8fc4..00000000 --- a/framework/src/ant/apache-ant-1.9.6/manual/Tasks/local.html +++ /dev/null @@ -1,186 +0,0 @@ -<!-- - Licensed to the Apache Software Foundation (ASF) under one or more - contributor license agreements. See the NOTICE file distributed with - this work for additional information regarding copyright ownership. - The ASF licenses this file to You under the Apache License, Version 2.0 - (the "License"); you may not use this file except in compliance with - the License. You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software - distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the License for the specific language governing permissions and - limitations under the License. ---> -<html> - -<head> -<meta http-equiv="Content-Language" content="en-us"> -<link rel="stylesheet" type="text/css" href="../stylesheets/style.css"> -<title>Local Task</title> -</head> - -<body> - -<h2>Local</h2> -<h3>Description</h3> -<p>Adds a local property to the current scope. Property scopes exist at Apache Ant's -various "block" levels. These include targets as well as the -<a href="parallel.html">Parallel</a> and <a href="sequential.html">Sequential</a> -task containers (including <a href="macrodef.html">Macrodef</a> bodies). A local -property at a given scope "shadows" properties of the same name at higher scopes, -including the global scope. Note that using the Local task at the global -level effectively makes the property local to the "anonymous target" in which -top-level operations are carried out; it will not be defined for other targets -in the buildfile. <b>Since Ant 1.8</b></p> - -<p>A property is made local if the <code><local></code> task - precedes its definition. See the examples section.</p> - -<h3>Parameters</h3> -<table border="1" cellpadding="2" cellspacing="0"> - <tr> - <td valign="top"><b>Attribute</b></td> - <td valign="top"><b>Description</b></td> - <td align="center" valign="top"><b>Required</b></td> - </tr> - <tr> - <td valign="top">name</td> - <td valign="top">The property to declare in the current scope</td> - <td valign="top" align="center">Yes</td> - </tr> -</table> - -<h3>Examples</h3> - -<h4>Temporarily shadow a global property's value</h4> - -<pre> - <property name="foo" value="foo"/> - - <target name="step1"> - <echo>Before local: foo is ${foo}</echo> - <local name="foo"/> - <property name="foo" value="bar"/> - <echo>After local: foo is ${foo}</echo> - </target> - - <target name="step2" depends="step1"> - <echo>In step2: foo is ${foo}</echo> - </target> -</pre> - -<p>outputs</p> - -<pre> -step1: - [echo] Before local: foo is foo - [echo] After local: foo is bar - -step2: - [echo] In step2: foo is foo -</pre> - -<p>here the local-task shadowed the global definition - of <code>foo</code> for the remainder of the target step1.</p> - -<h4>Creating thread local properties</h4> - -<pre> - <property name="foo" value="foo"/> - - <parallel> - <echo>global 1: foo is ${foo}</echo> - <sequential> - <local name="foo"/> - <property name="foo" value="bar.1"/> - <echo>First sequential: foo is ${foo}</echo> - </sequential> - <sequential> - <sleep seconds="1"/> - <echo>global 2: foo is ${foo}</echo> - </sequential> - <sequential> - <local name="foo"/> - <property name="foo" value="bar.2"/> - <echo>Second sequential: foo is ${foo}</echo> - </sequential> - <echo>global 3: foo is ${foo}</echo> - </parallel> -</pre> - -<p>outputs something similar to</p> - -<pre> - [echo] global 3: foo is foo - [echo] global 1: foo is foo - [echo] First sequential: foo is bar.1 - [echo] Second sequential: foo is bar.2 - [echo] global 2: foo is foo -</pre> - -<h4>Use inside macrodef</h4> - -<p>This probably is where local can be applied in the most useful - way. If you needed a "temporary property" inside a macrodef in Ant - prior to Ant 1.8.0 you had to try to come up with a property name - that would be unique across macro invocations.</p> - -<p>Say you wanted to write a macro that created the parent directory - of a given file. A naive approach would be:</p> - -<pre> - <macrodef name="makeparentdir"> - <attribute name="file"/> - <sequential> - <dirname property="parent" file="@{file}"/> - <mkdir dir="${parent}"/> - </sequential> - </macrodef> - <makeparentdir file="some-dir/some-file"/> -</pre> - -<p>but this would create a global property "parent" on the first - invocation - and since properties are not mutable, any subsequent - invocation will see the same value and try to create the same - directory as the first invocation.</p> - -<p>The recommendation prior to Ant 1.8.0 was to use a property name - based on one of the macro's attributes, like</p> - -<pre> - <macrodef name="makeparentdir"> - <attribute name="file"/> - <sequential> - <dirname property="parent.@{file}" file="@{file}"/> - <mkdir dir="${parent.@{file}}"/> - </sequential> - </macrodef> -</pre> - -<p>Now invocations for different files will set different properties - and the directories will get created. Unfortunately this "pollutes" - the global properties space. In addition it may be hard to come up - with unique names in some cases.</p> - -<p>Enter <code><local></code>:</p> - -<pre> - <macrodef name="makeparentdir"> - <attribute name="file"/> - <sequential> - <local name="parent"/> - <dirname property="parent" file="@{file}"/> - <mkdir dir="${parent}"/> - </sequential> - </macrodef> -</pre> - -<p>Each invocation gets its own property name "parent" and there will - be no global property of that name at all.</p> - -</body> -</html> - |