Hello World!
I'm talking about Boolean expressions in Alice3.
Boolean  expressions means that we can compare
if one value is less than another.
Let's start with just a very simple program I have an integer score.
Its value is going to be the value of the user types in
when I say "What did you get on the test?"
I want to, initially, simply tell if they passed or not.
So we drag an if in,  and we pick true as a placeholder.
if we click on that true, you'll see a lot of choices here.
We're going to be interested in comparing a whole number.
We can't compare decimal numbers because we're working with score
which is an integer.   An integer as a whole number,
We have a choice of these comparisons.
We can compare if the first value is less than the second value
Or the first value is less than or equal to the second value.
we can see if the first value is greater than the second value.
If the first value is greater than or equal to the second value,
Equal equal,  to ='s means that they are the same value.
The exclamation point with an equal, != , means they are NOT equal.
(Let's make this window a  little smaller so you can see the code better.)
I want to say if they passed or failed.
I could either check if their score is less than 65,
if their score is less than 65, I could use
this one and compare their score
to 65: a custom whole number and 65.
If their score is less than 65, I need to say
I need somebody to say this right?
Let's just go and add somebody to tell them their score.
(Pick the mad hatter.)
OK. Let's go back to edit our code.  If the score  core is less than 65,
I'm going to have the Mad Hatter say:
"You failed."
The else is optional, but let's put something in there and have him say "You passed."
OK. If we put in exactly 65,
this is false:  65 is not less than 65.
So that would be false and we would execute the command in the else part.
If we put in 65,  it says "passed", which is correct for 65.
Let's say we put in 64.
64 is less than 65, that is true.
The Mad Hatter is going to say, "You failed."
Let's run that:  "What did you get on the test?"
When you're testing some code like this idea to test
the number were comparing, like 65 and he says "You passed."  That's correct.
Let's run that again and let's put in a 64
and it says "You failed."  So that's good.
We could have done this the other way around:
I could have said the score was greater than or equal to 65.
Then we would swap these,  let's just do that.
So we put in a true to start with
and this time I'm going to pick greater than or equal to.
Again, we're going to have score is greater than
a custom whole number for my second choice and 65.
If the score is greater than or equal to 65, I'm going to have the Mad Hatter  say
"That's great"
and for the else I'm going to have him say
"Oh, too bad."
Notice that the opposite of less than <  is greater than or equal to >=.
if we didn't have that equal to, it would tell us that 65 didn't pass.
So let's run this.
And again I'm going to put in 65 to test that and he says
"You passed,  that's great!"
and if I put in 64 he says "You failed.  Oh, too bad."
I could actually put 2 statements into one of those.
I don't really need this one, I did that for comparison.
Let's just comment that out, make that disabled.
and if the score is less than 65, if that is true,
He says "You failed",  he says "That's great", "You passed",
And that's it for now.