UML14 — OCL: Numeric constants missing

The OCL chapter of the UML reference insists that not only there
is a data type Real, but one can also write constants of this type.
However, the OCL grammar does not allow for floating-point
constants.

To correct that, the rule for numbers:

number := ["0"-"9"] (["0"-"9"])*

could be rewritten as:

number := ["0"-"9"] (["0"-"9"])*
( "." ["0"-"9"] (["0"-"9"])* )?
( ("e" | "E") ( "+" | "-" )? ["0"-"9"] (["0"-"9"])* )?

to allow all traditional forms of Real constants, both with decimal
point and with exponent (and both).

The one mandatory digit after the decimal point is there on purpose,
to make sure that in an OCL string like

1..10

(which is perfectly legal inside the OCL collection literal) the
leftmost sub-string '1.' will not be incorrectly recognized as a real
constant. This little trick allows writing lexical parser for the OCL
that does not need more than one-character look-ahead.

Proposed resolution:

Agreed.
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