Important: It is now time to start putting code in your own .mint files. You will find that the interactive interpreter doesn't handle multi-line control flow structures.|
The when statement is the simplest of the control flow statements.
When a when statement's condition is true, it executes the next line. Otherwise it skips the next line.
If you have ever used the languages Java, C, or C++, you should know that a Mint
when statement is equivalent to an if statement with no curly braces in any of those languages.
a = -154 when a < 0 print "a is less than 0." //Will be printed. when a > 0 print "a is greater than 0." //Won't be printed.The if statement is the cousin to the when statement. When an if statement begins, it opens a clause.
A clause must be closed with an end statement. If the if statement's condition is true, it executes the clause.
Otherwise, the clause is ignored.
For Java, C, and C++, the Mint if statement and its corresponding end statement is the same as an if statement that does have curly braces.
a = 200 b = 300 if a == 200 and b == 300 show "a is two hundred and" //This clause will be executed. print " b is three hundred." end a *= 2 b *= 2 if a == 500 and b == 600 show "a is five hundred and" //This clause won't be executed. print " b is six hundred." endIf statements can take an optional else clause, which executes in the event that the if statement is false.
show "What is your name? " name = input if name == "Jack" print "Hello, Jack!" else print "Who are you?" endThere's also a thing called the if ... else if ... else statement which represents a chain of if statements:
import time today = weekdayNumber() if today == 0 print "Sunday" else if today == 1 print "Monday" else if today == 2 print "Tuesday" else if today == 3 print "Wednesday" else if today == 4 print "Thursday" else if today == 5 print "Friday" else print "Saturday" endThe above if ... else if ... else statement will print the current day of week.
Notice that we did 'import time', which imports a library known as time into the current scope.
This allows us to call the subprogram weekdayNumber and get the current day
of the week as a number. There will be more info about subprograms later.
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