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

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

In the second calling sequence, where K is a specified type name, the type command checks whether expr is a nonempty list whose entries are of type K.  That is, type(expr, nonemptylist(K)) returns true if type(expr, nonemptylist) 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/listlist

type/list

$L≔\left[x^4-1\,x^2\,x+3\right]$

$L≔\left[x^4-1\,x^2\,x+3\right]$

$\mathrm{type}\left(L\,\mathrm{nonemptylist}\right)$

$\mathrm{true}$

$\mathrm{type}\left(L\,\mathrm{nonemptylist}\left(\mathrm{polynom}\left(\mathrm{integer}\,x\right)\right)\right)$

$\mathrm{true}$

$\mathrm{type}\left(\left[\right]\,\mathrm{nonemptylist}\right)$

$\mathrm{false}$