2.4.1 Decimal Literals
1
{literal (decimal)}
A
decimal_literal is a
numeric_literal in the conventional decimal
notation (that is, the base is ten).
Syntax
2
decimal_literal ::= numeral [.
numeral] [
exponent]
3
numeral ::= digit {[
underline]
digit}
4
exponent ::= E [+]
numeral | E –
numeral
4.1/2
5
An exponent for
an integer literal shall not have a minus sign.
5.a
Ramification: Although this rule is in
this subclause, it applies also to the next subclause.
Static Semantics
6
An underline character in a numeric_literal
does not affect its meaning. The letter E of an exponent
can be written either in lower case or in upper case, with the same meaning.
6.a
Ramification: Although these rules are
in this subclause, they apply also to the next subclause.
7
An exponent indicates
the power of ten by which the value of the decimal_literal
without the exponent is to be multiplied to
obtain the value of the decimal_literal with
the exponent.
Examples
8
Examples of decimal
literals:
9
12 0 1E6 123_456 -- integer literals
12.0 0.0 0.456 3.14159_26 -- real literals
Wording Changes from Ada 83
9.a
We have changed the syntactic category name
integer to be numeral.
We got this idea from ACID. It avoids the confusion between this and
integers. (Other places don't offer similar confusions. For example,
a string_literal is different from a string.)
Sponsored by Ada-Europe