Instructions

210Compiler

Text="hello world"

Len=StringLength(Text)

End Sub

In main the reference of text is presented as parameters to the function StringLength. If in a function

a normal parameter is changed then the change is not visible outside this function. With references

this is different. Through parameter str can in StringLength the contents of text be changed since str

is only the reference (pointer) to the array variable text.

Presently arrays can only be presented "by Reference"!

Pointer Arithmetic

In the current C-Control Pro software also arithmetic on a reference (pointer) is permitted, as the fol-

lowing example shows. The arithmetic is limited to addition, subtraction, multiplication and division.

Sub main()

Dim Len As Integer

Dim Text(15) As Char

Text="hello world"

Len=StringLength(Text+2*3)

End Sub

Pointer arithmetic is currently experimental and may possibly still contain errors.

Strings as Parameter

Since Version 2.0 of the IDE it is possible to call functions with a string as parameter. The called

function gets the string as reference. Since references are RAM based and predefined strings are

stored in the flash memory, the compiler creates internally an anonymous variable, and copies the

data from flash into memory.

Sub StringLength(ByRef str As Char) As Integer

....

End Sub

Sub main()

Dim Len As Integer

Len=StringLength("hallo welt")

End Sub

4.3.8 Tables