Request for Enhancement to MapKey()

[akj]

Given:

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NewMap Country.s()
Country("US") = "United States"
Country("FR") = "France"
Country("GE") = "Germany"

Please enhance MapKey() so that

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Debug MapKey(Country(), "France") ; The result is "FR"

is functionally equivalent to

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ForEach Country()
  If Country()="France"
    Debug MapKey(Country())
    Break
  EndIf
Next

It would also be useful to have a case-sensitivity flag along the lines of:

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Debug MapKey(Country(), "France", #PB_Map_NoCase)

[Little John]

The elements of a Map() are not always unique. For instance, we can have

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NewMap Country.s()
Country("US") = "democracy"
Country("FR") = "democracy"
Country("GE") = "democracy"

According to your suggestion, what should be the result of

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Debug MapKey(Country(), "democracy")

Regards, Little John

[akj]

@Little John:

"US"

[Kaeru Gaman]

why not "FR"? it's first in alphabeth...
since Maps have no indices, the order should be undefined, so you cannot say it should be the element you declared first.

[Little John]

@Little John:

"US"

Why? IMHO the correct result would be "US", "FR" and "GE". But MapKey() only returns one key.

Regards, Little John

[freak]

Who sais a map can contain only strings ?

[akj]

@Freak:

I don't think anyone was saying that maps can contain only strings.
The example I chose to illustrate my request just happened to be string based.
My example is generalisable to any map type including structures.

[freak]

The MapKey() function needs to have a fixed type for its arguments (PB has no polymorphic functions), so how would you handle strings and structures then ?

Besides, this kind of reverse lookup is awfully slow and as you have shown above it can be easily done in just a few lines, so i don't think there is a need for a built in function.