contract
========

The contract module provides helper functions to assist in enforcing the
contracts of your class methods, such as requiring an int or a string
parameter.

Contract
--------

static number(name, x)
++++++++++++++++++++++

Aborts the fiber with an error if ``x`` is not a number. The ``name`` parameter
should be the name of the parameter from which ``x`` is derived.

static int(name, x)
+++++++++++++++++++

Aborts the fiber with an error if ``x`` is not an integer. The ``name``
parameter should be the name of the parameter from which ``x`` is derived.

static uint(name, x)
++++++++++++++++++++

Aborts the fiber with an error if ``x`` is not a positive integer or zero. The
``name`` parameter should be the name of the parameter from which ``x`` is
derived.

static string(name, x)
++++++++++++++++++++++

Aborts the fiber with an error if ``x`` is not a string. The ``name`` parameter
should be the name of the parameter from which ``x`` is derived.