index on number type differentiates between integer and decimal notation

[sanderr]

Actionables

ISO7 only!

• make number behave like float: make an explicit decimal point required for the number type. The number(x) cast should be verified to work so it can be used to assign int values to number types.
• create the float alias for number because it more clearly conveys what it means. Update documentation to use float rather than number.
• verify that lsm and inmanta-lsm can work with this new float type

Motivation

An index on an attribute of type number only considers a number expressed respectively with and without .0 to be diffferent, while these are just different representations of the same number. As an example, the following model prints False.

entity A:
    number x
end

implement A using std::none

index A(x)


std::print(A(x=0) == A(x=0.0))

[sanderr]

Indexes seem to be built using repr, which comes across as very brittle to me:

inmanta-core/src/inmanta/ast/entity.py

Line 384 in 0c5ce06

attributes = {k: repr(v.get_value()) for (k, v) in instance.slots.items() if v.is_ready()}

[sanderr]

Discussed in planning meeting:

• make number behave like float:̶ m̶a̶k̶e̶ ̶a̶n̶ ̶e̶x̶p̶l̶i̶c̶i̶t̶ ̶d̶e̶c̶i̶m̶a̶l̶ ̶p̶o̶i̶n̶t̶ ̶r̶e̶q̶u̶i̶r̶e̶d̶ ̶f̶o̶r̶ ̶t̶h̶e̶ ̶n̶u̶m̶b̶e̶r̶ ̶t̶y̶p̶e̶. The number(x) cast should be verified to work so it can be used to assign int values to number types.
• create the float alias for number because it more clearly conveys what it means. Update documentation to use float rather than number.
• add testcases: description: should work + index lookup on float with int should work