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Synopsis Retrieve a list element via its index.
Syntax Exp1 [ Exp2 ]
Types
Exp1 Exp2 Exp1 [ Exp2 ]
list[T1] int T1
Description List subscription uses the integer value of Exp2 as index in the list value of Exp1. The value of Exp2 should be greater or equal 0 and less than the number of elements in the list. If this is not the case, the exception IndexOutOfBounds is thrown.
Examples Introduce a list, assign it to L and retrieve the element with index 1: 
rascal>L = [10, 20, 30];
list[int]: [10,20,30]
rascal>L[1];
int: 20
Explore an error case: 
rascal>L[5];
|stdin:///|(2,1,<1,2>,<1,3>): IndexOutOfBounds(5)
	at ___SCREEN_INSTANCE___(|stdin:///|(0,5,<1,0>,<1,5>))

Questions
Question [1]. For a list of length N, legal index value are:







Question [2].
Given 
L = [17, -20, 6, 2];

L[2] ==



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