En esta página, tú vas a continuar desarrollando un juego para adivinar un número, en esta oportunidad recibiremos los intentos del jugador, comparando con el resultado correcto hasta que se adivine la respuesta correcta.
You learned about loops on Unit 1 Lab 3 Page 6: Looping with a Counter.
You've seen conditionals on Unit 1 Lab 2 Page 5: Adding Variety to Gossip and Unit 1 Lab 5 Page 2: Sprite Following a Sprite.
You'll want the computer to ask players to guess again and again until they guess correctly. To do that, you will use the 
block. Repeat until is a loop (just like repeat, forever, and for) but also a conditional (like if and if else). It repeats until a certain condition is met. For this program, the code should repeat until the player's answer equals the secret number.
repeat until to ask the player (
) to guess the secret number until their 
equals the secret number.script variables block to use it.ask and answer blocks go together. If you use ask to ask a question, the user's answer will be reported by answer.
would be written as
DISPLAY("Why did the chicken cross the road?")
userResponse ← INPUT()
.
INPUT()accepts the value from the user and returns that input value, which is then assigned to the variable
userResponsewith the
←syntax. In Snap!, this is just like how
answer accepts a value from the user and reports it, and that report is what the computer sets the variable user response to.Repeat until makes its decision based on the output of a hexagonal predicate block.
Why is Boolean capitalized?
The word Boolean is capitalized because it's named after a person, George Boole, who invented the branch of mathematics dealing with Boolean operations (such as and, or, and not).
A predicate is a hexagon-shaped reporter that asks a true/false question such as these examples:
Predicates report a Boolean value (either 
or 
).
Predicates fit into a hexagonal input slots of conditionals, such as in 
and . Predicates help conditionals decide when to do something.
The if and if-else blocks are called conditionals because they control the code based on a true-or-false condition.
Which inputs to 
mystery function will report "finished"?
repeat until loop will stop, and the function will report "finished."
report command isn't inside the if.
repeat until block checks the value of input every time through the loop, not just its initial value.
What will the sprite say if you run the same function with the input 1?
repeat until work?
repeat until block runs the code in its script slot until input = 5, then the computer skips down to the next command, report (finished), without the sprite ever saying 5.
repeat until block tests the value of input before running the code in its script slot.
What will happen if you run the same function with the input 9?
if block do when input is 9?
set instruction do to the value of input?
if command run?
if command will not run.
join to merge the text "You guessed it! My secret number was" with the value of the secret number variable.