Function: oo
Section: conversions
C-Name: mkoo
Prototype:
Help: oo=oo(): infinity.
Doc: returns an object meaning $+\infty$, for use in functions such as
 \kbd{intnum}. It can be negated (\kbd{-oo} represents $-\infty$), and
 compared to real numbers (\typ{INT}, \typ{FRAC}, \typ{REAL}), with the
 expected meaning: $+\infty$ is greater than any real number and $-\infty$ is
 smaller.
