prefix let
Documentation for prefix let
assembled from the following types:
language documentation Operators
From Operators
(Operators) prefix let
sub prefix:<let>(Mu is rw)
Refers to a variable in an outer scope whose value will be restored if the block exits unsuccessfully, implying that the block returned a defined object.
my = "Jane Doe";say "We got $name";
This code provides a default name for $name
. If the user exits from the prompt or simply does not provide a valid input for $name
; let
will restore the default value provided at the top. If user input is valid, it will keep that.
language documentation Variables
From Variables
(Variables) prefix let
Restores the previous value if the block exits unsuccessfully. A successful exit means the block returned a defined value or a list.
my = 42;say ;
In the above case, if the Bool.pick
returns true, the answer will stay as 84 because the block returns a defined value (say
returns True
). Otherwise the die
statement will cause the block to exit unsuccessfully, resetting the answer to 42.