gistfile1.pyw

'''
Created on Apr 7, 2010

@author: filo
'''
from nipype.interfaces.base import traits, isdefined, TraitedSpec
from enthought.traits.trait_base import _Undefined

class OutputMultiPath(traits.List):
 
    def get(self, object, name):
        value = self.get_value(object, name)
        if len(value) == 0:
            return _Undefined()
        elif len(value)==1:
            return value[0]
        else:
            return value
    
    def set(self, object, name, value):
        self.set_value(object, name,self.validate(object,name,value))
    
    def validate(self, object, name, value):
        if not isdefined(value):
            return value
        newvalue = value
        if isinstance(value, str):
            newvalue = [value]
        return super(OutputMultiPath, self).validate(object, name, newvalue)

        
class InputMultiPath(traits.List):
    
    def validate(self, object, name, value):
        if not isdefined(value):
            return value
        newvalue = value
        if isinstance(value, str):
            newvalue = [value]
        return super(InputMultiPath, self).validate(object, name, newvalue)


class Test(TraitedSpec):
    foo = OutputMultiPath(traits.File())
    boo = InputMultiPath(traits.File())
    koo = traits.List()
    
    
t = Test()
print t.foo
t.foo = 'abc'
print t.foo
t.foo = ['abc']
print t.foo        
t.foo = 'abc'
print t.foo
t.foo = ['abc', 'abc']
print t.foo

print t.boo
t.boo = 'abc'
print t.boo
t.boo = ['abc']
print t.boo        
t.boo = 'abc'
print t.boo

t.boo = ['abc', 'abc']
print t.boo

print t.koo
print isdefined(t.koo)

t.foo = 67

very nice. this works great including the undefined