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33 lines
624 B
33 lines
624 B
<?php
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/**
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* 箭头函数时匿名函数的简洁版
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* fn(参数)=>表达式
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*/
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//匿名函数
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$a = function($n){
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return $n*$n;
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};
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echo "使用匿名函数".$a(3).PHP_EOL;
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//箭头函数
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$b=fn($n) => $n*$n;
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echo "使用箭头函数".$b(3).PHP_EOL;
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//2 箭头函数不用use，会自动继承父类的变量
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$c=5;
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//匿名函数
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$fn1=function() use ($c){
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return $c * $c;
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};
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echo $fn1().PHP_EOL;
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//箭头函数
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$fn2=fn()=>$c*$c; //这里箭头函数不用形参，就能使用父类中的$c
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echo $fn2().PHP_EOL;
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?>
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