Unless, Until, and While
The unless
statement is structured similarly to an if
statement.
unless condition
#thing to be done if the condition is false
end
It is basically the reverse of the if statement, because if
statements will only be done if the condition is true
, but the unless
statement will only be done if the condition is false
. The else
keyword can also be used inside unless
statements.
while
statements repeat a block of code as long as a condition is true
.
while condition
#something to do
end
until
statements are the opposite of while
statements; they repeat until a condition becomes true
. Here is their syntax:
until condition
#something to do
end
Important!
Make sure that you don't make an infinite loop. An infinite loop repeats forever, stopping your program from ever advancing, because the condition never changes to what will stop the loop. Exercise
Make a while or until statement from scratch that will puts
"I'm looping!" to the console 7 times.