For more infomation about this bug, visit <https://www.fmtc.be/bugzilla/orocos/show_bug.cgi?id=516>

           Summary: [Scripting]No conversions available from int -> double -
                    >float etc.
           Product: RTT
           Version: rtt-trunk
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Real-Time Toolkit (RTT)
        AssignedTo: orocos-dev at lists [dot] mech [dot] kuleuven [dot] be
        ReportedBy: peter.soetens at fmtc [dot] be
                CC: orocos-dev at lists [dot] mech [dot] kuleuven [dot] be
   Estimated Hours: 0.0

There is sometimes a lot of confusion when a scripting methodi takes a float
argument and the user writes plain '3.0' (a double), which is rejected by the
parser.

In the RTT, it is possible to define constructor functions like:

 var double d = double(4) // convert int to double

For these 1-to-1 conversions, the scripting engine could look up the
constructor table of double() itself and see if it is possible to construct a
double from an int. That would allow you to write:

 var double d = 4 // automatic construction of a double from an int

A lot of newcomers have been bitten by this, and the constructor infrastructure
is already in place. Only the automatic lookup needs to be done at the right
places, which is a small patch.

We could have the following conversion table:

Automatic:
float ->[double]
double ->[float]
int ->[double, float]
char ->[int, uint]

Automatic, with a warning:
float -> [int, uint]
double-> [int, uint]
int -> [uint]
uint -> [int]

Any other suggestions ?

To supress the warnings, we could require the user to write C++ style casts:

 var int i = int(3.333) 

for example.

Peter