These functions return true if expr is of the specified type, and false otherwise.

An expression is of type relation if it is of type $\mathrm{`=`}$, `$\mathrm{<>}$`, $\mathrm{`<`}$, or `$\mathrm{<=}$`.

For each of the types f, where f is one of $\mathrm{`=`}$, `$\mathrm{<>}$`, $\mathrm{`<`}$, or `$\mathrm{<=}$`, x is of type f if op(0, x) = f.

Note: Expressions formed using the operators > and >= are automatically converted to expressions of type `<` and `<=`, respectively.

type/=, type/<>, type/<, type/<=

type/boolean

$\mathrm{type}\left(x<5\&comma;\mathrm{relation}\right)$

$\mathrm{true}$

$\mathrm{type}\left(a\mathbf{or}\mathbf{not}b\&comma;\mathrm{relation}\right)$

$\mathrm{false}$

$\mathrm{type}\left(1<2\mathbf{and}5<x\&comma;\mathrm{relation}\right)$

$\mathrm{true}$