Chapter5.General Language Features of M

Chapter5.General Language Features of M

Table of Contents

Data Types

Numeric Expressions

Numeric Accuracy

Integer Expressions

Truth-valued Expressions

M Names

Variables

Arrays and Subscripts

M Collation Sequences

Local Variables

Global Variables and Resource Name Environments

Naked References

Global Variable Name Environments

Literals

String Literals

Numeric Literals

Expressions

Operators

Precedence

Arithmetic Operators

Logical Operators

String Operators

Numeric Relational Operators

String Relational Operators

Pattern Match Operator

Commands

Postconditionals

Timeouts

Interrupt Handling

M Locks

Intrinsic Functions

Intrinsic Special Variables

Routines

Lines

Entry References

Label References

Indirection

Argument Indirection

Atomic Indirection

Entryref Indirection

Pattern Code Indirection

Name Indirection

Indirection Concerns

Parameter Passing

Actuallists

Actualnames

Formallists

Formallabel

Parameter Passing Operation

Parameter Passing Mechanisms

GT.M Parameter Passing Extensions

External Calls

Extrinsic Functions

Extrinsic Special Variables

Transaction Processing

TP Definitions

Key Considerations - Writing TP Code

TP Performance

TP Example

This chapter describes general features of the M language, as well as general information about the operation of GT.M. Commands, Functions, and Intrinsic Special Variables are each described in separate chapters. This chapter contains information about exceptions, as well as information about general M features.

MUMPS is a general purpose language with an embedded database system. This section describes the features of the language that are not covered as Commands, Functions, or Intrinsic Special Variables chapters.