In the first calling sequence, the type command checks if expr is a valid nonempty Maple set. It returns true if expr is a set containing at least one element and false otherwise.

See the set help page for a description of the set datatype.

In the second calling sequence, where K is a specified type name, the type command checks whether expr is a nonempty set whose entries are of type K.  That is, type(expr, nonemptyset(K)) returns true if type(expr, nonemptyset) is true and type(x, K) is true for each entry x of expr.

See the type help page for a description of valid types in Maple.

type/set

$S≔\left\{1\,2\,\frac{3}{2}\right\}$

$S≔\left\{1\,2\,\frac{3}{2}\right\}$

$\mathrm{type}\left(S\,\mathrm{nonemptyset}\right)$

$\mathrm{true}$

$\mathrm{type}\left(S\,\mathrm{nonemptyset}\left(\mathrm{rational}\right)\right)$

$\mathrm{true}$

$\mathrm{type}\left(S\,\mathrm{nonemptyset}\left(\mathrm{integer}\right)\right)$

$\mathrm{false}$

$\mathrm{type}\left(\varnothing \,\mathrm{nonemptyset}\right)$

$\mathrm{false}$