QMap -> what does .contains() compare?
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Hello there,
running Qt 6.6 am wondering, what the .contains() method of QMap uses to compare.
The documentation says
"Returns true if the map contains an item with key key; otherwise returns false."
For me that sounds too generic to be sure - I mean, it could be a hash-value get´s created behind the scenes, or the memory address ocupied is sompared.ChatGPT said it uses the default comparsion operator defined of the class type used as KEY.
-> Is that correct? And if so, where do I find that information?Given it is, how do I know which of let´s say QTime overloaded operators is the default comparsion one?
A lovely day for a ̶g̶̶u̶̶i̶̶n̶̶n̶̶e̶̶s̶ DUFF^^
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Hello there,
running Qt 6.6 am wondering, what the .contains() method of QMap uses to compare.
The documentation says
"Returns true if the map contains an item with key key; otherwise returns false."
For me that sounds too generic to be sure - I mean, it could be a hash-value get´s created behind the scenes, or the memory address ocupied is sompared.ChatGPT said it uses the default comparsion operator defined of the class type used as KEY.
-> Is that correct? And if so, where do I find that information?Given it is, how do I know which of let´s say QTime overloaded operators is the default comparsion one?
@Flaming-Moe said in QMap -> what does .contains() compare?:
Hello there,
running Qt 6.6 am wondering, what the .contains() method of QMap uses to compare.
The documentation says
"Returns true if the map contains an item with key key; otherwise returns false."
For me that sounds too generic to be sure - I mean, it could be a hash-value get´s created behind the scenes, or the memory address ocupied is sompared.Hash is generated in
QHash, not inQMap.ChatGPT said it uses the default comparsion operator defined of the class type used as KEY.
-> Is that correct? And if so, where do I find that information?Yes.
Given it is, how do I know which of let´s say QTime overloaded operators is the default comparsion one?
The one which overloads the comparison:
bool opearator==(const QTime &other) const. -
Hello there,
running Qt 6.6 am wondering, what the .contains() method of QMap uses to compare.
The documentation says
"Returns true if the map contains an item with key key; otherwise returns false."
For me that sounds too generic to be sure - I mean, it could be a hash-value get´s created behind the scenes, or the memory address ocupied is sompared.ChatGPT said it uses the default comparsion operator defined of the class type used as KEY.
-> Is that correct? And if so, where do I find that information?Given it is, how do I know which of let´s say QTime overloaded operators is the default comparsion one?
@Flaming-Moe said in QMap -> what does .contains() compare?:
"Returns true if the map contains an item with key key; otherwise returns false."
For me that sounds too generic to be sure - I mean, it could be a hash-value get´s created behind the scenes, or the memory address ocupied is sompared.Comparing means operator==(), or do you compare your stuff with something else?
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Okay I was not aware, that == is the compare operator
since others are also overloaded
bool operator<=(QTime lhs, QTime rhs) bool operator==(QTime lhs, QTime rhs) bool operator>(QTime lhs, QTime rhs) bool operator>=(QTime lhs, QTime rhs)
