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))
Something you may not realize is that the addjacent-concatenation occurs
at compile time, so your third example could be transformed from:
print(
'Calculating fibonacci_old, fibonacci_memoize and '
'to determine speed increase'
'fibonacci_memoize once for {0} '.format(large_fibonacci))
to:
print(
'Calculating fibonacci_old, fibonacci_memoize and '
'to determine speed increase'
'fibonacci_memoize once for {0}'
' '.format(large_fibonacci))
All three literals are combined before format() is called. Knowing this
could be vital if you had {} elsewhere in the 9single) literal.
--
DaveA
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