Ada Reference Manual, ISO/IEC 8652:1995(E) with COR.1:2000

Ada Reference Manual

ISO/IEC 8652:1995(E)

with Technical Corrigendum 1

Language and Standard Libraries

Copyright 1992,1993,1994,1995 Intermetrics, Inc.

Copyright 2000 The MITRE Corporation, Inc.

Ada Reference Manual - Language and Standard Libraries

Copyright 1992, 1993, 1994, 1995, Intermetrics, Inc.

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Technical Corrigendum 1

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ISO/IEC 8652:1995(E) with COR.1:2000 Ada Reference Manual

i 15 June 2001 Table of Contents

Table of ContentsTable of Contents............................................................................................................ i

Foreword to this version of the Ada Reference Manual ........................................... ix

Foreword........................................................................................................................ xi

Introduction .................................................................................................................. xii

Section 1: General.......................................................................................................... 11.1 Scope.......................................................................................................................................... 1

1.1.1 Extent .................................................................................................................................. 11.1.2 Structure ............................................................................................................................. 21.1.3 Conformity of an Implementation with the Standard....................................................... 41.1.4 Method of Description and Syntax Notation..................................................................... 51.1.5 Classification of Errors ...................................................................................................... 6

1.2 Normative References............................................................................................................... 71.3 Definitions.................................................................................................................................. 8

Section 2: Lexical Elements.......................................................................................... 92.1 Character Set ............................................................................................................................. 92.2 Lexical Elements, Separators, and Delimiters....................................................................... 102.3 Identifiers ................................................................................................................................. 112.4 Numeric Literals ...................................................................................................................... 12

2.4.1 Decimal Literals................................................................................................................ 122.4.2 Based Literals................................................................................................................... 12

2.5 Character Literals .................................................................................................................... 132.6 String Literals .......................................................................................................................... 132.7 Comments................................................................................................................................ 142.8 Pragmas ................................................................................................................................... 142.9 Reserved Words ...................................................................................................................... 17

Section 3: Declarations and Types ............................................................................ 193.1 Declarations............................................................................................................................. 193.2 Types and Subtypes................................................................................................................ 20

3.2.1 Type Declarations............................................................................................................. 213.2.2 Subtype Declarations....................................................................................................... 233.2.3 Classification of Operations............................................................................................ 24

3.3 Objects and Named Numbers................................................................................................. 243.3.1 Object Declarations.......................................................................................................... 263.3.2 Number Declarations ....................................................................................................... 28

3.4 Derived Types and Classes .................................................................................................... 293.4.1 Derivation Classes ........................................................................................................... 31

3.5 Scalar Types ............................................................................................................................ 323.5.1 Enumeration Types .......................................................................................................... 363.5.2 Character Types ............................................................................................................... 373.5.3 Boolean Types.................................................................................................................. 383.5.4 Integer Types .................................................................................................................... 383.5.5 Operations of Discrete Types.......................................................................................... 413.5.6 Real Types ........................................................................................................................ 423.5.7 Floating Point Types ........................................................................................................ 433.5.8 Operations of Floating Point Types ................................................................................ 453.5.9 Fixed Point Types............................................................................................................. 45

ISO/IEC 8652:1995(E) with COR.1:2000 Ada Reference Manual

Table of Contents 15 June 2001 ii

3.5.10 Operations of Fixed Point Types ................................................................................... 473.6 Array Types .............................................................................................................................. 48

3.6.1 Index Constraints and Discrete Ranges ......................................................................... 503.6.2 Operations of Array Types............................................................................................... 523.6.3 String Types...................................................................................................................... 53

3.7 Discriminants ........................................................................................................................... 533.7.1 Discriminant Constraints ................................................................................................. 563.7.2 Operations of Discriminated Types................................................................................. 57

3.8 Record Types ........................................................................................................................... 573.8.1 Variant Parts and Discrete Choices ...............................................