weird python issue

[mdipierro]

does anybody understand this?

massimo-di-pierros-macbook:web2py mdipierro$ python web2py.py -S
welcome
>>> print INPUT() or 'oops'
oops

why is INPUT same as False?

Massimo

[DenesL]

Reposting from http://groups.google.com/group/web2py/browse_thread/thread/2114e5ab590fc228#

From the python 2.5 manual, library reference, 3.1:

"The following values are considered false:
...
instances of user-defined classes, if the class defines a __nonzero__
() or __len__() method, when that method returns the integer zero or
bool value False."

Both INPUT and A derive from DIV which has a __len__ method defined as
len(self.components).
INPUT's len is zero while A's is one, so combining that with the 'or'
in sqlhtml rev979 line 319 gives the above mentioned results.

Denes

[mdipierro]

thanks. I forgot DIV had a len method.

Massimo

On May 31, 10:27 pm, DenesL <denes1...@yahoo.ca> wrote:
> Reposting fromhttp://groups.google.com/group/web2py/browse_thread/thread/2114e5ab59...