Ada Programming/Attributes/'First

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Description

X'First, where X is any scalar subtype (for example integer, enumerated, real), is an attribute that represents the first value (lower bound) in the range of X.

A'First, where A is an array, denotes the first index value. For more-dimensional arrays, A'First(N) denotes the first index value of the Nth dimension (N must be static).

Example

type My_Enum is (Enum1, Enum2, Enum3); type My_Int isrange -1 .. 5; ... pragmaAssert (My_Enum'First = Enum1); -- OKpragmaAssert (My_Int'First = -1); -- OKpragmaAssert (My_Int'First = 0); -- Wrong!

See also

Wikibook

• Ada Programming
• Ada Programming/Attributes
• Last
• Range

Ada Reference Manual

• 13.3 Operational and Representation Attributes(Annotated)
• Annex K Language-Defined Attributes(Annotated)