Method Chaining in future versions of Clarion

community Feature Requests
1

Asking for language changes has had a positive effect on my other posts on the SV newsgroup. For example, the ability to assign procedures to arrays.

It’s time for Clarion to have the capability that TS-M2 had in the 90s, which is to chain (method chaining) functions like this:

d = A.Call().Call2().Call3()

For example, today, working with cJson, it would be very important to chain calls to functions to reduce the creation of functions.

2

That would be really cool.

One thing I’ve done in the past for MS Excel COM from Clarin, was pass a dot-delimited string containing the object names and the respective properties/methods (such as font stuff). Then my Clarion class would parse the string and associate the objects/properties/etc at run-time. These were COM objects, but could easily be Clarion objects too. It really saved a lot of time (except for the time writing it).

3

Wouldn’t this simply mean, being able to return a class from a function?
Can’t we already?

4

This code gives a compilation error.
Interesting is that the same IDE supports the containment of functions/methods.

    program

    map
    end
    
TA              class(),type
i                   long(0)
Call                procedure(),*TA
Show                procedure()
Test                procedure()
                END !* TA *
A           &TA
B           &TA
    CODE
    A &= new( TA )
    B &= A.Call().Call().Call().Call().Call();
    B.Show()

TA.Call    procedure()
    code
    self.I = self.I + 5
    RETURN self
	
TA.Test     procedure()
    code
	
TA.Show	    procedure()
    code
    message( right( self.I, 10 ) )

image

5

FWIW, as per the implicit SELF first parameter, you can do:
B &= Call(Call(Call(Call(A.Call()))));
and
B &= Call(Call(Call(Call(Call(A)))));

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