If e is a long double constant, and it is perfectly representable as a
double constant, convert it to a double constant.
Note that this must NOT be done in contexts where there are no further
operations, since then it could change the type (eg, in the function call
printf("%La", 2.0L); the 2.0 must stay as a long double).
The D Programming Language's Unofficial Docs
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If e is a long double constant, and it is perfectly representable as a double constant, convert it to a double constant. Note that this must NOT be done in contexts where there are no further operations, since then it could change the type (eg, in the function call printf("%La", 2.0L); the 2.0 must stay as a long double).