Re: how?

Subject: Re: how?
From: Yvan KOENIG <email@hidden>
Date: Sun, 10 Jan 2010 22:15:34 +0100

Le 10 janv. 2010 à 21:55, Jack Schwart a écrit :

Hi, I am trying to teach myself applescript. I went through Jerry Lee Ford, Jr.'s book, Applescript for the Absolute Beginner, and understood everything except this following code block. Can any one help me figure out how the variable "ValidInput" switches to "true" and ends the loop?

Thanks, Jack

--******** GetPlayerInput handler ******************

--This handler prompts the player to tell the game the range of
--numbers from which lottery ticket numbers should be selected
on GetPlayerInput()

--This variable is used to control loop execution
set ValidInput to false

repeat until ValidInput = true -- loop until valid input is collected

--Question,:how does ValidInput switch to true???

--Prompt the player to specify the range of numbers to be used
set NoRange to text returned of (display dialog ¬
"What is the highest number that can be selected when " & ¬
"creating a lottery ticket?" default answer ¬
"44" buttons {"OK"} with title GameTitle)
--The range must be at least 3 and no larger than 59
if (NoRange > 2) and (NoRange < 60) then
set NoRange to NoRange as integer --Convert the player input
--Question: Why do I need this step???? A: see page 101 "Coercion"
return NoRange -- Return the player's input
else -- Display an error message if the input is not valid
display dialog "Error: You must enter an integer value " & ¬
"between 3 and 59" with title GameTitle
end if

end repeat

end GetPlayerInput

In fact the variable ValidInput is not changed.

It's absolutely useless in the handler.

The loop is exited when the instruction

return NoRange is executed.

The handler may be edited as:

on getplayerinput()

repeat -- loop until valid input is collected

--Prompt the player to specify the range of numbers to be used

set NoRange to text returned of (display dialog ¬

"What is the highest number that can be selected when " & ¬

"creating a lottery ticket?" default answer ¬

"44" buttons {"OK"} with title GameTitle)

--The range must be at least 3 and no larger than 59

if (NoRange > 2) and (NoRange < 60) then

set NoRange to NoRange as integer --Convert the player input

--Question: Why do I need this step???? A: see page 101 "Coercion"

return NoRange -- Return the player's input

else -- Display an error message if the input is not valid

display dialog "Error: You must enter an integer value " & ¬

"between 3 and 59" with title GameTitle

end if

end repeat

end getplayerinput

or :