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9.4.2.3 Constants

GDB allows you to express the constants of Modula-2 in the following ways:

• Integer constants are simply a sequence of digits. When used in an expression, a constant is interpreted to be type-compatible with the rest of the expression. Hexadecimal integers are specified by a trailing `H', and octal integers by a trailing `B'.

• Floating point constants appear as a sequence of digits, followed by a decimal point and another sequence of digits. An optional exponent can then be specified, in the form `E[+|-]nnn', where `[+|-]nnn' is the desired exponent. All of the digits of the floating point constant must be valid decimal (base 10) digits.

• Character constants consist of a single character enclosed by a pair of like quotes, either single (') or double ("). They may also be expressed by their ordinal value (their ASCII value, usually) followed by a `C'.

• String constants consist of a sequence of characters enclosed by a pair of like quotes, either single (') or double ("). Escape sequences in the style of C are also allowed. See section C and C++ constants, for a brief explanation of escape sequences.

• Enumerated constants consist of an enumerated identifier.

• Boolean constants consist of the identifiers TRUE and FALSE.

• Pointer constants consist of integral values only.

• Set constants are not yet supported.