syntax - What do curly braces in Java mean by themselves? -

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i have java code uses curly braces in 2 ways

// curly braces attached 'if' statement: if(node.getid() != null) {     node.getid().apply(this); }  // curly braces themselves: {     list<pexp> copy = new arraylist<pexp>(node.getargs());     for(pexp e : copy)     {         e.apply(this);     } } outamethodexp(node);

what stand-alone curly braces after first if statement mean?

the purpose of braces provide scope-limit. list<pexp> copy exist within braces, , have no scope outside of them.

if generated code, assume code-generator can insert code (such this) without having worry how many times has inserted list<pexp> copy , without having worry possibly renaming variables if snippet inserted same method more once.


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