<documentation title="Lowercase Built-In functions">
<standard>
<![CDATA[
All PHP built-in functions should be lowercased when called.
]]>
</standard>
<code_comparison>
<code title="Valid: Lowercase function call.">
<![CDATA[
if (<em>isset</em>($foo)) {
echo $foo;
}
]]>
</code>
<code title="Invalid: isset not called as lowercase.">
<![CDATA[
if (<em>isSet</em>($foo)) {
echo $foo;
}
]]>
</code>
</code_comparison>
</documentation>