Dynamic variable names: Difference between revisions

=={{header|FreeBASIC}}==

FreeBASIC is a statically typed, compiled language and so it is not possible to create new variables, dynamically, at run time. However, you can make it look to the user like you are doing so with code such as the following. Ideally, a 'map' should be used for an exercise such as this but, as there isn't one built into FB, I've used a dynamic array instead which is searched linearly for the variable name.

<lang freebasic>' FB 1.05.0 Win64

Type DynamicVariable

As String name

As String value

End Type

Function FindVariableIndex(a() as DynamicVariable, v as String, nElements As Integer) As Integer

v = LCase(Trim(v))

For i As Integer = 1 To nElements

If a(i).name = v Then Return i

Next

Return 0

End Function

Dim As Integer n, index

Dim As String v

Cls

Do

Input "How many variables do you want to create (max 5) "; n

Loop Until n > 0 AndAlso n < 6

Dim a(1 To n) As DynamicVariable

Print

Print "OK, enter the variable names and their values, below"

For i As Integer = 1 to n

Print

Print " Variable"; i

Input " Name : ", a(i).name

a(i).name = LCase(Trim(a(i).name)) ' variable names are not case sensitive in FB

If i > 0 Then

index = FindVariableIndex(a(), a(i).name, i - 1)

If index > 0 Then

Print " Sorry, you've already created a variable of that name, try again"

i -= 1

Continue For

End If

End If

Input " Value : ", a(i).value

a(i).value = LCase(Trim(a(i).value))

Next

Print

Print "Press q to quit"

Do

Print

Input "Which variable do you want to inspect "; v

If v = "q" OrElse v = "Q" Then Exit Do

index = FindVariableIndex(a(), v, n)

If index = 0 Then

Print "Sorry there's no variable of that name, try again"

Else

Print "It's value is "; a(index).value

End If

Loop

End</lang>

Sample input/output :

{{out}}

<pre>

How many variables do you want to create (max 5) ? 3

OK, enter the variable names and their values, below

Variable 1

Name : a

Value : 1

Variable 2

Name : b

Value : 2

Variable 3

Name : b

Sorry, you've already created a variable of that name, try again

Variable 3

Name : c

Value : 4

Press q to quit

Which variable do you want to inspect ? b

It's value is 2

Which variable do you want to inspect ? c

It's value is 4

Which variable do you want to inspect ? a

It's value is 1

Which variable do you want to inspect ? q

</pre>