Name Rascal/Patterns/Abstract/Node

Synopsis Node in abstract pattern.

Syntax Name ( Pat1, Pat2, ..., Patn )

Description A node pattern matches a node value or a datatype value, provided that Name matches with the constructor symbol of that value and Pat1, Pat2, ..., Patn match the children of that value in order.

Examples Match on node values (recall that the function symbol of a node has to be quoted, see Values/Node):

rascal>import IO;
ok
rascal>if("f"(A,13,B) := "f"("abc", 13, false))
>>>>>>>   println("A = <A>, B = <B>");
A = abc, B = false
ok

Define a data type and use it to match:

rascal>data Color = red(int N) | black(int N);
ok
rascal>if(red(K) := red(13))
>>>>>>>   println("K = <K>");
K = 13
ok

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