HP 3000 Manuals HP 3000 Manuals
Operators
An operator specifies an operation to be performed on one or more
operands.
Syntax
operator ::= One selected from the set
[ ] ( ) . ->
++ -- & * + - ~ ! sizeof
/ % << >> < > <= >= !=
^ | && || ? : = == *=
/= %= += -= <<= >>= &= ^= |=
, # ##
Description
Operator representations may require one, two, or three characters. The
compiler matches the longest sequence to find tokens. For example,
a+++++b
is parsed as if it had been written
a++ ++ + b
which results in a syntax error. An alternate parse
a++ + ++b
is not chosen because it does not follow the longest first rule, even
though it results in a syntactically correct expression. As a result,
white space is often important in writing expressions that use complex
operators. The precedence of operators is discussed in more detail in
Chapter 5.
The obsolete form of the assignment operators (=* instead of *=) is not
supported. If this form is used, the compiler parses it as two tokens (=
and *).
The operators [ ], ?:, and ( ) (function call operator) occur only in
pairs, possibly separated by expressions. You can use some operators as
either binary operators or unary operators. Often the meaning of the
binary operator is much different from the meaning of the unary operator.
For example, binary multiply and unary indirection:
a * b versus *p