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       <img src="" class="logo" alt=""><h1>Register compute bindings</h1>
       <small class="dont-index">Source: <a href="https://github.com/apache/arrow/blob/main/r/R/dplyr-funcs.R" class="external-link"><code>R/dplyr-funcs.R</code></a></small>
       <div class="d-none name"><code>register_binding.Rd</code></div>
     </div>

     <div class="ref-description section level2">
     <p><code>register_binding()</code> is used to populate a list of functions that operate on
 (and return)
 Expressions. These are the basis for the <code>.data</code> mask inside dplyr methods.</p>
     </div>

     <div class="section level2">
     <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
     <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">register_binding</span><span class="op">(</span><span class="va">fun_name</span>, <span class="va">fun</span>, notes <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="fl">0</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
     </div>

     <div class="section level2">
     <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>
     <dl><dt>fun_name</dt>
 <dd><p>A string containing a function name in the form <code>"function"</code> or
 <code>"package::function"</code>.</p></dd>


 <dt>fun</dt>
 <dd><p>A function, or <code>NULL</code> to un-register a previous function.
 This function must accept <code>Expression</code> objects as arguments and return
 <code>Expression</code> objects instead of regular R objects.</p></dd>


 <dt>notes</dt>
 <dd><p>string for the docs: note any limitations or differences in
 behavior between the Arrow version and the R function.</p></dd>

 </dl></div>
     <div class="section level2">
     <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>


 <p>The previously registered binding or <code>NULL</code> if no previously
 registered function existed.</p>
     </div>
     <div class="section level2">
     <h2 id="writing-bindings">Writing bindings<a class="anchor" aria-label="anchor" href="#writing-bindings"></a></h2>


 <ul><li><p><code>Expression$create()</code> will wrap any non-Expression inputs as Scalar
 Expressions. If you want to try to coerce scalar inputs to match the type
 of the Expression(s) in the arguments, call
 <code>cast_scalars_to_common_type(args)</code> on the
 args. For example, <code>Expression$create("add", args = list(int16_field, 1))</code>
 would result in a <code>float64</code> type output because <code>1</code> is a <code>double</code> in R.
 To prevent casting all of the data in <code>int16_field</code> to float and to
 preserve it as int16, do
 <code>Expression$create("add", args = cast_scalars_to_common_type(list(int16_field, 1)))</code></p></li>
 <li><p>Inside your function, you can call any other binding with <code>call_binding()</code>.</p></li>
 </ul></div>

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	<img src="" class="logo" alt=""><h1>Register compute bindings</h1>
	<small class="dont-index">Source: <a href="https://github.com/apache/arrow/blob/main/r/R/dplyr-funcs.R" class="external-link"><code>R/dplyr-funcs.R</code></a></small>
	<div class="d-none name"><code>register_binding.Rd</code></div>
	</div>

	<div class="ref-description section level2">
	<p><code>register_binding()</code> is used to populate a list of functions that operate on
	(and return)
	Expressions. These are the basis for the <code>.data</code> mask inside dplyr methods.</p>
	</div>

	<div class="section level2">
	<h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
	<div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">register_binding</span><span class="op">(</span><span class="va">fun_name</span>, <span class="va">fun</span>, notes <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="fl">0</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
	</div>

	<div class="section level2">
	<h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>
	<dl><dt>fun_name</dt>
	<dd><p>A string containing a function name in the form <code>"function"</code> or
	<code>"package::function"</code>.</p></dd>


	<dt>fun</dt>
	<dd><p>A function, or <code>NULL</code> to un-register a previous function.
	This function must accept <code>Expression</code> objects as arguments and return
	<code>Expression</code> objects instead of regular R objects.</p></dd>


	<dt>notes</dt>
	<dd><p>string for the docs: note any limitations or differences in
	behavior between the Arrow version and the R function.</p></dd>

	</dl></div>
	<div class="section level2">
	<h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>


	<p>The previously registered binding or <code>NULL</code> if no previously
	registered function existed.</p>
	</div>
	<div class="section level2">
	<h2 id="writing-bindings">Writing bindings<a class="anchor" aria-label="anchor" href="#writing-bindings"></a></h2>


	<ul><li><p><code>Expression$create()</code> will wrap any non-Expression inputs as Scalar
	Expressions. If you want to try to coerce scalar inputs to match the type
	of the Expression(s) in the arguments, call
	<code>cast_scalars_to_common_type(args)</code> on the
	args. For example, <code>Expression$create("add", args = list(int16_field, 1))</code>
	would result in a <code>float64</code> type output because <code>1</code> is a <code>double</code> in R.
	To prevent casting all of the data in <code>int16_field</code> to float and to
	preserve it as int16, do
	<code>Expression$create("add", args = cast_scalars_to_common_type(list(int16_field, 1)))</code></p></li>
	<li><p>Inside your function, you can call any other binding with <code>call_binding()</code>.</p></li>
	</ul></div>

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