implicitly concats of adjacent strings does not work with format

Cecil Westerhof Cecil at decebal.nl
Wed Apr 29 16:40:31 CEST 2015


Op Wednesday 29 Apr 2015 15:14 CEST schreef Dave Angel:

> On 04/29/2015 08:42 AM, Cecil Westerhof wrote:
>> I have the folowing print statements:
>> print(
>> 'Calculating fibonacci_old, fibonacci_memoize and '
>> 'fibonacci_memoize once for {0} '.format(large_fibonacci))
>>
>>
>> print(
>> 'Calculating fibonacci_old, fibonacci_memoize and '
>> 'fibonacci_memoize once for {0} '.format(large_fibonacci) +
>> 'to determine speed increase')
>>
>> print(
>> 'Calculating fibonacci_old, fibonacci_memoize and '
>> 'to determine speed increase'
>> 'fibonacci_memoize once for {0} '.format(large_fibonacci))
>>
>>
>> print(
>> 'Calculating fibonacci_old, fibonacci_memoize and '
>> 'fibonacci_memoize once for {0} '.format(large_fibonacci)
>> 'to determine speed increase')
>>
>> The first three work, but the last gives:
>> 'to determine speed increase')
>> ^
>> SyntaxError: invalid syntax
>>
>> Not very important, because I can use the second one, but I was
>> just wondering why it goes wrong.
>>
>
> Adjacent string literals are concatenated. But once you've called a
> method (.format()) on that literal, you now have an expression, not
> a string literal.
>
> You could either change the last line to
>
> + 'to determine speed increase')
>
> or you could concatenate all the strings before calling the format
> method:
>
>
> print(
> 'Calculating fibonacci_old, fibonacci_memoize and '
> 'fibonacci_memoize once for {0} '
> 'to determine speed increase' .format(large_fibonacci))

I now use this, I did not know that the addjacent-concatenation
occurred at compile time.
I spend a ‘little‘ time, but it was worth it.

>From the amount of messages you could think I am a spammer. ;-)

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof



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