Since there was talk of if-then-else not being allowed in lambda expressions, the following is from "Dive into Python"

[Casey Hawthorne]

Since there was talk of if-then-else not being allowed in lambda
expressions, the following is from "Dive into Python"

The and-or conditional expression trick from page 41 of "Dive into
Python"

Wrap the arguments in lists and then take the first element.

>>a = ""
b = "second"
(1 and [a] or [b])[0]

''

--
Regards,
Casey

[Peter Otten]

Casey Hawthorne wrote:

Since there was talk of if-then-else not being allowed in lambda
expressions, the following is from "Dive into Python"

The and-or conditional expression trick from page 41 of "Dive into
Python"

Wrap the arguments in lists and then take the first element.

>>>a = ""
b = "second"
(1 and [a] or [b])[0]

''

# python 2.5

>>a, b = "", 0
a if False else b

0

>>a if True else b

''

Time to tear out that page. Really.

Peter

[Ant]

# python 2.5

>a, b = "", 0
a if False else b

0

>a if True else b

''

Time to tear out that page. Really.

Not quite - 2.5 hasn't been released in its final version yet, and many
projects I should imagine will take a while to upgrade.

[Peter Otten]

Ant wrote:

>

># python 2.5

>>a, b = "", 0
a if False else b

0

>>a if True else b

''

Time to tear out that page. Really.

Not quite - 2.5 hasn't been released in its final version yet, and many
projects I should imagine will take a while to upgrade.

Ok, use

if cond:
value = ... # expression that must not be evaluated unless it absolutely
# has to be
else:
value = ... # same thing

which will withstand the test of time. Now tear out that page...

Peter

[Bruno Desthuilliers]

Peter Otten wrote:

Ant wrote:

>>># python 2.5

>>a, b = "", 0
>>a if False else b

0

>>a if True else b

''

Time to tear out that page. Really.

Not quite - 2.5 hasn't been released in its final version yet, and many
projects I should imagine will take a while to upgrade.

Ok, use

if cond:
value = ... # expression that must not be evaluated unless it absolutely
# has to be
else:
value = ... # same thing

which will withstand the test of time.

But isn't allowed in a lambda !-)

--
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in 'o****@xiludom.gro'.split('@')])"

[Peter Otten]

Bruno Desthuilliers wrote:

But isn't allowed in a lambda !-)

Then tear out that lambada page, too, I was tempted to say, but I will
desist. For now...

Peter