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<a href="../../../html/index.html">Home</a> » <a href="../../../html/pmc.html">PMCs</a> » Iterator PMC
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<h1><a name="NAME"
>NAME</a></h1>
<p>src/pmc/iterator.pmc - Iterator PMC</p>
<h1><a name="DESCRIPTION"
>DESCRIPTION</a></h1>
<p>These are the vtable functions for the Iterator base class.
Iterators are used in combination with other classes(mainly aggregates) to visit all entries in that aggregate.</p>
<h1><a name="SYNOPSIS"
>SYNOPSIS</a></h1>
<h2><a name="default_usage"
>default usage</a></h2>
<pre> .local pmc iterator, array, entry
iterator = iter array
iter_loop:
unless iterator, iter_end # while (more values)
entry = shift iterator # get an entry
...
goto iter_loop
iter_end:</pre>
<h2><a name="iterate_from_the_end,_for_arrays"
>iterate from the end, for arrays</a></h2>
<pre> .local pmc iterator, array, entry
iterator = iter array
iterator = .ITERATE_FROM_END
iter_loop:
unless iterator, iter_end # while (more values)
entry = pop iterator # get an entry
...
goto iter_loop
iter_end:</pre>
<h2><a name="iterate_over_a_hash"
>iterate over a hash</a></h2>
<pre> .local pmc iterator, hash, key, entry
iterator = iter hash
iter_loop:
unless iterator, iter_end # while (more values)
key = shift iterator # get the key..
entry = hash[key]
...
goto iter_loop
iter_end:</pre>
<h1><a name="Methods"
>Methods</a></h1>
<dl>
<dt><a name="void_init()"
><b><code>void init()</b></code></a></dt>
Raises an exception. Use <code>init_pmc()</code>.
<dt><a name="void_init_pmc(PMC_*initializer)"
><b><code>void init_pmc(PMC *initializer)</b></code></a></dt>
Initializes the iterator with an aggregate PMC. Defaults iteration mode to iterate from start.
<dt><a name="INTVAL_get_integer_keyed(PMC_*key)"
><b><code>INTVAL get_integer_keyed(PMC *key)</b></code></a></dt>
<dt><a name="FLOATVAL_get_number_keyed(PMC_*key)"
><b><code>FLOATVAL get_number_keyed(PMC *key)</b></code></a></dt>
<dt><a name="STRING_*get_string_keyed(PMC_*key)"
><b><code>STRING *get_string_keyed(PMC *key)</b></code></a></dt>
<dt><a name="PMC_*get_pmc_keyed(PMC_*key)"
><b><code>PMC *get_pmc_keyed(PMC *key)</b></code></a></dt>
Returns the element for <code>*key</code>.
<dt><a name="INTVAL_exists_keyed(PMC_*key)"
><b><code>INTVAL exists_keyed(PMC *key)</b></code></a></dt>
Returns whether an element for <code>*key</code> exists in the aggregate.
<dt><a name="INTVAL_defined()"
><b><code>INTVAL defined()</b></code></a></dt>
Returns whether the iterator contains an aggregate.
<dt><a name="INTVAL_defined_keyed(PMC_*key)"
><b><code>INTVAL defined_keyed(PMC *key)</b></code></a></dt>
<dt><a name="void_set_integer_native(INTVAL_value)"
><b><code>void set_integer_native(INTVAL value)</b></code></a></dt>
Restart iterator</dl>
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