Why does replace not replace?

Question

code:

a = 'g'
b = a.title()
b.replace(b, a)
print(b)

output: G

I think the output should be 'g' lowercase as the replace statement replaces the uppercase 'G' to lowercase one.

I am trying to solve a challenge in which I have to capitalize a string but not the one that starts with numerals?

replace is not "in place" it returns the replaced string. so do something like c = b.replace(b, a) — Nullman
– Nullman, Commented Feb 10, 2021 at 10:50

Nidal Barada · Accepted Answer · 2021-02-10 10:52:59Z

3

You have to assign the value of b.replace(b, a) to the variable b before you print it.

a = 'g'
b = a.title()
b = b.replace(b, a)
print(b)

Output:

answered Feb 10, 2021 at 10:52

Nidal Barada

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Comments

Jack Lilhammers · Accepted Answer · 2021-02-10 16:08:23Z

2

Strings in python are immutable.
Functions that would change the string, return a new one instead.

answered Feb 10, 2021 at 10:54

Jack Lilhammers

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T1Berger · Accepted Answer · 2021-02-10 10:55:32Z

2

The output of replace need ot be reassign - because replace gives you a copy with the replaced changes - so it isnt in place!

a = 'g'
b = a.title()
b = b.replace(b, a)
print(b)

answered Feb 10, 2021 at 10:55

T1Berger

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