The call type(x, `global`) returns true if x is both of type symbol and a global variable, and false otherwise.

The name global is a keyword and therefore it must be enclosed by backquotes in a call to type.

If the parameter t is included, it will check that x is assigned something of that type.

type/symbol

$\mathrm{type}\left(x\,\mathrm{`global`}\right)$

$\mathrm{true}$

$\mathrm{type}\left(\mathrm{convert}\left(x\,\mathrm{`local`}\right)\,\mathrm{`global`}\right)$

$\mathrm{false}$

f := proc() global a; a end proc:

$z≔f\left(\right)$

$z≔a$

$\mathrm{type}\left(z\,\mathrm{`global`}\right)$

$\mathrm{true}$