validoot 1.0

Basic example:

from validoot import validates, inst, typ, between

@validates(inst(basestring), typ(int), between(0, 100))
def do_something(name, id, age):
    pass

In the code above, a validoot.ValidationError will be thrown if the name is not a string or unicode, if the id is not an integer, or if the age is not between 0 and 100.

Operators:

We can extend the first example by adding an additional check for the name: it must be between 5 and 40 characters. For this we use the validoot.And operator to combine the clauses.

from validoot import validates, inst, typ, between, len_between, And

@validates(And(inst(basestring), len_between(5, 40)), typ(int), between(0, 100))
def do_something(name, id, age):
    pass

An Or operator also exists. Both And and Or take in a variable number of clauses and can be nested further.

Operator shortcuts are provided for joining clauses in a different manner which reads differently (._and(...), ._or(...)). So our previous example can be changed to look like this:

from validoot import validates, inst, typ, between, len_between

@validates(inst(basestring)._and(len_between(5, 40)), typ(int), between(0, 100))
def do_something(name, id, age):
    pass

Keyword arguments:

There is also support for keyword arguments:

from validoot import validates, inst, typ

@validates(inst(basestring), something=typ(float))
def do_something(name, something=1.0, anotherthing=2):
    pass

Here the something value must pass the validation checks as specified in the decorator. No checks exist for anotherthing so it has no restrictions.

Additional Clauses:

There are some more complex clauses included with the package:

• _ : The underscore only allows NoneType.

• numeric : Only accepts int, float, or long types.

• text : Only accepts instances of basestring (Python 2) or str (Python 3).

These can be found in the validoot.builtins module.

FAQ:

from validoot import validates, inst, between

@validates(inst(basestring), None, between(0, 100))
def do_something(name, id, age):
    pass