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Type Specifier SATISFIES

Compound Type Specifier Kind:


Compound Type Specifier Syntax:

satisfies predicate-name

Compound Type Specifier Arguments:

predicate-name---a symbol.

Compound Type Specifier Description:

This denotes the set of all objects that satisfy the predicate predicate-name, which must be a symbol whose global function definition is a one-argument predicate. A name is required for predicate-name; lambda expressions are not allowed. For example, the type specifier (and integer (satisfies evenp)) denotes the set of all even integers. The form (typep x '(satisfies p)) is equivalent to (if (p x) t nil).

The argument is required. The symbol * can be the argument, but it denotes itself (the symbol *), and does not represent an unspecified value.

The symbol satisfies is not valid as a type specifier.

The following X3J13 cleanup issue, not part of the specification, applies to this section:

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