3.3. Strings are Immutable¶
Even though you can manipulate a string to create a new string the original string is
immutable which means that they never change. Notice that after you execute the
code below the string stored in the variable
sentence hasn’t changed.
While the strings themselves can’t be changed you can change the value of a variable. This throws away the original string and sets the variable’s value to the new string.
We can reassign a variable to hold the result of calling a function on a string. On line
3 of the example below, we make the new value of
sentence be the result of changing
the old value of
sentance after it was changed to lower case.
We always do all the work on the right side of
= and then store the result into
the variable listed on the left side.