Name
dict_dec_or_remove — Decrement a counter in a dictionary of counters or deletes it if it becomes zero or negative.
Synopsis
dict_dec_or_remove ( |
inout dict dictionary , |
| in key any , | |
in value_decrement integer
); |
Description
The function checks whether dict contains key . If it isn't so then the
function checks the datatype of the value associated with the key.
An error 42000 is signalled in case of non-integer value or a
negative integer value. If the value is positive and greater than
value_decrement then
value_decrement is
subtracted from it and the result become the new value associated
with key in dict . If the value is positive and
less than or equal to value_decrement then key is removed from dict . If key is not in the
dictionary then the dictionary remains unchanged.
Informally, the function reverts the effect of dict_inc_or_add .
Parameters
dict
Dictionary of counters. The NULL value is equivalent to an empty dictionary.
key
Key of a dictionary item to process.
value decrement
A nonnegative integer (typically 1) that is subtracted from the
value associated with key
.
Return Types
The function returns the changed value associated with the
key , or zero in any other
case.