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Top Forums Shell Programming and Scripting Newbie question: modulo operator with negative operand, bug or feature? Post 302951892 by jim mcnamara on Tuesday 11th of August 2015 12:13:48 PM
Old 08-11-2015
@Scrutinizer - what did you try, the original code? The '$((' '))' construct requires spaces around it I believe.

NO! it does not need spaces, just leading spaces

I'm wrong - the $(( does not require spaces it is part of command substitution (from opnegroup.org):
Quote:
If the current character is an unquoted '$' or '`', the shell shall identify the start of any candidates for parameter expansion ( Parameter Expansion), command substitution ( Command Substitution), or arithmetic expansion ( Arithmetic Expansion) from their introductory unquoted character sequences: '$' or "${", "$(" or '`', and "$((", respectively.
But since that is true then why do we get wacky (divergent) results with POSIX-compliant shells? my ksh did not like it. My bash (3.4.3) did after I added some spaces. It specifically complained about %5. Hmm.
 

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DROP 
OPERATOR(7) PostgreSQL 9.2.7 Documentation DROP OPERATOR(7) NAME
DROP_OPERATOR - remove an operator SYNOPSIS
DROP OPERATOR [ IF EXISTS ] name ( { left_type | NONE } , { right_type | NONE } ) [ CASCADE | RESTRICT ] DESCRIPTION
DROP OPERATOR drops an existing operator from the database system. To execute this command you must be the owner of the operator. PARAMETERS
IF EXISTS Do not throw an error if the operator does not exist. A notice is issued in this case. name The name (optionally schema-qualified) of an existing operator. left_type The data type of the operator's left operand; write NONE if the operator has no left operand. right_type The data type of the operator's right operand; write NONE if the operator has no right operand. CASCADE Automatically drop objects that depend on the operator. RESTRICT Refuse to drop the operator if any objects depend on it. This is the default. EXAMPLES
Remove the power operator a^b for type integer: DROP OPERATOR ^ (integer, integer); Remove the left unary bitwise complement operator ~b for type bit: DROP OPERATOR ~ (none, bit); Remove the right unary factorial operator x! for type bigint: DROP OPERATOR ! (bigint, none); COMPATIBILITY
There is no DROP OPERATOR statement in the SQL standard. SEE ALSO
CREATE OPERATOR (CREATE_OPERATOR(7)), ALTER OPERATOR (ALTER_OPERATOR(7)) PostgreSQL 9.2.7 2014-02-17 DROP OPERATOR(7)
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