String Subscription

rascal-0.42.2

Synopsis

Retrieve a substring via its index.

Syntax

Exp₁ [ Exp₂ ]

Types

Exp₁	Exp₂	Exp₁ [ Exp₂ ]
str	int	str

Description

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

Examples

Introduce a string, assign it to S and retrieve the element with index 1:

rascal>S = "abc";
str: "abc"
───
abc
───
rascal>S[1];
str: "b"
───
b
───

Explore an error case:

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