Subs parameters

[agraham]

Originally Posted by mjcoon

Yes, the relaxed implicit-variant treatment of local variables does not work for arrays. This is because all elements of the array have to have the same variant for the indexing mechanism to work

You are making it sound much more complicated than it really is, it is really very simple. Normal variables, both global and local are just string variables. Arrays of the type they are declared as or strings if no type is specified. Numeric operations are always performed on Doubles and variables and arrays are coerced to and from Doubles when required for arithmetic operations. Boolean values are represented as the strings "true" and "false".

[merli]

Originally Posted by agraham

You are making it sound much more complicated than it really is, it is really very simple. Normal variables, both global and local are just string variables. Arrays of the type they are declared as or strings if no type is specified. Numeric operations are always performed on Doubles and variables and arrays are coerced to and from Doubles when required for arithmetic operations. Boolean values are represented as the strings "true" and "false".

Do I understand it right that all the time I am using variable in program, Basic converts this variable from string "12345678.9876543" to value? If yes isn't it much time and processor consuming?

[agraham]

Yes you understand it right and yes it takes up more CPU cycles during mathematical operations compared to using strongly typed variables but that is the price you pay for the simplicity and ease of use of a weakly typed language and in most applications, even on a device, this is usually not a problem as there are other things that dominate execution time - like the user for many interactive applications.

If you really need to do intensive mathematics in Basic4ppc you can declare one or more arrays or structs as Double and use their elements for numeric calculations. As all numeric operations are done as Doubles this avoids converting to and from string values. In an optimised compiled app this will give you a good speed boost over normal string based non-array variables. To avoid the overhead of the array access for each variable fetch and use non-array variables you could use my MathRecompiler performance enhancer library.

I believe Erel intends to introduce some form of type declaration for normal variables in some future release of Basic4ppc.

[Erel]

I believe Erel intends to introduce some form of type declaration for normal variables in some future release of Basic4ppc.

Next version will include it.
You will be able to declare the type of all variables (including sub parameters).
The main types will be Number which is mapped to .Net Double, Integer which is mapped to Int32 and String (or undeclared).