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+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE fileref SYSTEM "fileref.dtd">
+
+<fileref>
+ <header>
+ <copyright>
+ <year>2012</year><year>2015</year>
+ <holder>Ericsson AB. All Rights Reserved.</holder>
+ </copyright>
+ <legalnotice>
+ The contents of this file are subject to the Erlang Public License,
+ Version 1.1, (the "License"); you may not use this file except in
+ compliance with the License. You should have received a copy of the
+ Erlang Public License along with this software. If not, it can be
+ retrieved online at http://www.erlang.org/.
+
+ Software distributed under the License is distributed on an "AS IS"
+ basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ the License for the specific language governing rights and limitations
+ under the License.
+
+ </legalnotice>
+
+ <title>assert.hrl</title>
+ <prepared></prepared>
+ <docno></docno>
+ <date></date>
+ <rev></rev>
+ </header>
+ <file>assert.hrl</file>
+ <filesummary>Assert Macros</filesummary>
+ <description>
+ <p>The include file <c>assert.hrl</c> provides macros for inserting
+ assertions in your program code.</p>
+ <p>These macros are defined in the Stdlib include file
+ <c>assert.hrl</c>. Include the following directive in the module
+ from which the function is called:</p>
+ <code type="none">
+-include_lib("stdlib/include/assert.hrl").</code>
+ <p>When an assertion succeeds, the assert macro yields the atom
+ <c>ok</c>. When an assertion fails, an exception of type <c>error</c> is
+ instead generated. The associated error term will have the form
+ <c>{Macro, Info}</c>, where <c>Macro</c> is the name of the macro, for
+ example <c>assertEqual</c>, and <c>Info</c> will be a list of tagged
+ values such as <c>[{module, M}, {line, L}, ...]</c> giving more
+ information about the location and cause of the exception. All entries
+ in the <c>Info</c> list are optional, and you should not rely
+ programatically on any of them being present.</p>
+
+ <p>If the macro <c>NOASSERT</c> is defined when the <c>assert.hrl</c>
+ include file is read by the compiler, the macros will be defined as
+ equivalent to the atom <c>ok</c>. The test will not be performed, and
+ there will be no cost at runtime.</p>
+
+ <p>For example, using <c>erlc</c> to compile your modules, the following
+ will disable all assertions:</p>
+ <code type="none">
+erlc -DNOASSERT=true *.erl</code>
+ <p>(The value of <c>NOASSERT</c> does not matter, only the fact that it
+ is defined.)</p>
+ <p>A few other macros also have effect on the enabling or disabling of
+ assertions:</p>
+ <list type="bulleted">
+ <item>If <c>NODEBUG</c> is defined, it implies <c>NOASSERT</c>, unless
+ <c>DEBUG</c> is also defined, which is assumed to take
+ precedence.</item>
+ <item>If <c>ASSERT</c> is defined, it overrides <c>NOASSERT</c>, that
+ is, the assertions will remain enabled.</item>
+ </list>
+ <p>If you prefer, you can thus use only <c>DEBUG</c>/<c>NODEBUG</c> as
+ the main flags to control the behaviour of the assertions (which is
+ useful if you have other compiler conditionals or debugging macros
+ controlled by those flags), or you can use <c>ASSERT</c>/<c>NOASSERT</c>
+ to control only the assert macros.</p>
+
+ </description>
+
+ <section>
+ </section>
+
+ <section>
+ <title>Macros</title>
+ <taglist>
+ <tag><c>assert(BoolExpr)</c></tag>
+ <item><p>Tests that <c>BoolExpr</c> completes normally returning
+ <c>true</c>.</p>
+ </item>
+
+ <tag><c>assertNot(BoolExpr)</c></tag>
+ <item><p>Tests that <c>BoolExpr</c> completes normally returning
+ <c>false</c>.</p>
+ </item>
+
+ <tag><c>assertMatch(GuardedPattern, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> completes normally yielding a value
+ that matches <c>GuardedPattern</c>. For example:
+ <code type="none">
+ ?assertMatch({bork, _}, f())</code></p>
+ <p>Note that a guard <c>when ...</c> can be included:
+ <code type="none">
+ ?assertMatch({bork, X} when X > 0, f())</code></p>
+ </item>
+
+ <tag><c>assertNotMatch(GuardedPattern, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> completes normally yielding a value
+ that does not match <c>GuardedPattern</c>.</p>
+ <p>As in <c>assertMatch</c>, <c>GuardedPattern</c> can have a
+ <c>when</c> part.</p>
+ </item>
+
+ <tag><c>assertEqual(ExpectedValue, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> completes normally yielding a value
+ that is exactly equal to <c>ExpectedValue</c>.</p>
+ </item>
+
+ <tag><c>assertNotEqual(ExpectedValue, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> completes normally yielding a value
+ that is not exactly equal to <c>ExpectedValue</c>.</p>
+ </item>
+
+ <tag><c>assertException(Class, Term, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> completes abnormally with an exception
+ of type <c>Class</c> and with the associated <c>Term</c>. The
+ assertion fails if <c>Expr</c> raises a different exception or if it
+ completes normally returning any value.</p>
+ <p>Note that both <c>Class</c> and <c>Term</c> can be guarded
+ patterns, as in <c>assertMatch</c>.</p>
+ </item>
+
+ <tag><c>assertNotException(Class, Term, Expr)</c></tag>
+ <item><p>Tests that <c>Expr</c> does not evaluate abnormally with an
+ exception of type <c>Class</c> and with the associated <c>Term</c>.
+ The assertion succeeds if <c>Expr</c> raises a different exception or
+ if it completes normally returning any value.</p>
+ <p>As in <c>assertException</c>, both <c>Class</c> and <c>Term</c>
+ can be guarded patterns.</p>
+ </item>
+
+ <tag><c>assertError(Term, Expr)</c></tag>
+ <item><p>Equivalent to <c>assertException(error, Term,
+ Expr)</c></p>
+ </item>
+
+ <tag><c>assertExit(Term, Expr)</c></tag>
+ <item><p>Equivalent to <c>assertException(exit, Term, Expr)</c></p>
+ </item>
+
+ <tag><c>assertThrow(Term, Expr)</c></tag>
+ <item><p>Equivalent to <c>assertException(throw, Term, Expr)</c></p>
+ </item>
+
+ </taglist>
+ </section>
+
+ <section>
+ <title>SEE ALSO</title>
+ <p><seealso marker="compiler:compile">compile(3)</seealso></p>
+ <p><seealso marker="erts:erlc">erlc(3)</seealso></p>
+ </section>
+</fileref>