type(expr, _Inert) returns true if expr is an inert expression of the form generated by ToInert and suitable as input to FromInert.

type(expr, _Inert(F)) where F is a symbol returns true if expr is an inert expression of a specific form, corresponding to the symbol used for F.

For example, an expression is of type _Inert(LIST) if it is a function whose name part is the symbol _Inert_LIST, corresponding to the inert representation of a list.

The symbol F can be one of the following:

$e≔\mathrm{ToInert}\left(\left[2\,3.141593\,''tomato''\,y=x^2\right]\right)$

$e≔\mathrm{\_Inert\_LIST}\left(\mathrm{\_Inert\_EXPSEQ}\left(\mathrm{\_Inert\_INTPOS}\left(2\right)\,\mathrm{\_Inert\_FLOAT}\left(\mathrm{\_Inert\_INTPOS}\left(3141593\right)\,\mathrm{\_Inert\_INTNEG}\left(6\right)\right)\,\mathrm{\_Inert\_STRING}\left(''tomato''\right)\,\mathrm{\_Inert\_EQUATION}\left(\mathrm{\_Inert\_NAME}\left(''y''\right)\,\mathrm{\_Inert\_POWER}\left(\mathrm{\_Inert\_NAME}\left(''x''\right)\,\mathrm{\_Inert\_INTPOS}\left(2\right)\right)\right)\right)\right)$

$\mathrm{type}\left(e\,\mathrm{\_Inert}\right)$

$\mathrm{true}$

$\mathrm{type}\left(e\,\mathrm{\_Inert}\left(\mathrm{LIST}\right)\right)$

$\mathrm{true}$

$\mathrm{type}\left(e\,\mathrm{\_Inert}\left(\mathrm{SET}\right)\right)$

$\mathrm{false}$

The type/_Inert command was introduced in Maple 2021.

For more information on Maple 2021 changes, see Updates in Maple 2021.