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Node Subscription

rascal-0.34.0

Synopsis​

Retrieve an argument of a node via its index.

Syntax​

Exp₁ [ Exp₂ ]

Types​

Exp₁Exp₂Exp₁ [ Exp₂ ]
nodeintvalue

Description​

Node subscription uses the integer value of Exp₂ as index in the argument list of the node value of Exp₁. The value of Exp₂ should be greater or equal 0 and less than the number of arguments of the node. If this is not the case, the exception IndexOutOfBounds is thrown.

Examples​

Introduce a node, assign it to F and retrieve the various arguments:

rascal>F = "f"(1, "abc", false);
node: "f"(1,"abc",false)
rascal>F[0]
value: 1
rascal>F[1]
value: "abc"
rascal>F[2]
value: false

Explore an error case:

rascal>F[3];
|prompt:///|(2,1,<1,2>,<1,3>): IndexOutOfBounds(3)
    at $shell$(|prompt:///|(0,5,<1,0>,<1,5>))
ok