19 — Game: how fast are you?

The stopwatch from 15 — Time is enough for a game. Start the clock the moment the signal appears, and read it when the key comes down.

#Steps

1. Starting the clock and reading it is the whole idea:

   start the timer
   ask answer Press enter
   show elapsed
   

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   elapsed is the seconds since the clock was started.

2. Give the signal late. Asking straight away lets someone press early, so pause first:

   show Get ready
   wait 3 seconds
   show Press enter now
   

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3. Keeping the reading in a name lets you use it more than once:

   start the timer
   ask answer Enter
   set taken to elapsed
   show taken
   

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4. Say how fast that was:

   set taken to 0.4
   if taken is less than 1
       show very fast
   else if taken is less than 2
       show not bad
   else
       show a little slow
   end
   

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5. All of it together:

   show A reaction test
   show Get ready
   wait 3 seconds
   show Press enter now
   start the timer
   ask answer Enter
   set taken to elapsed
   show taken
   if taken is less than 1
       show very fast
   else if taken is less than 2
       show not bad
   else
       show a little slow
   end
   

   copyrun it →

   The clock gives the time up to the moment elapsed is read, so where you start it is exactly where the measuring begins.

#Try it yourself

Measure three times and show the best of them. Put each reading in a list and ask for the smallest of times — the list is from 05 — Set and the smallest is from 17 — Word guess.

#What you learned

• start the timer starts the clock and elapsed gives the seconds since.
• set taken to elapsed keeps a reading so it can be used again.
• A wait before the signal is what stops an early press.
• The reading is an ordinary number, so a condition takes it as it is.