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Re: Proper place for functions in KVC paths?

Hello,


I think the api implies they all work and will have differing outcomes depending on what you would like to 'sum' or 'count' etc. e.g., Consider the keypath: 'company.people.accounts.totalLiability'.

If I want to know how much is owed in total:
Number total = ( Number )company.valueForKeyPath ( "@sum.people.accounts.totalLiability" );

I am curious if you have actually used this? 

Obviously not enough! Bummer...

I meant company.valueForKeyPath ( "email@hiddenLiability" ) - but that's still wrong. You can only provide toOne keyPaths after @sum it seems (i.e., "email@hiddenLiability" ) which will succeed (having now tested).


You can think of the keypath as a tokenized string that is evaluated recursively through the elements toward the end of the string and the @operators are looking for scalar values to iterate over and accumulate. So, for company.people.account.totalLiability where people is the only array, then email@hiddenLiability would produce the sum as desired. Suppose, however, that each person had multiple accounts. The following would also be valid: email@hiddenemail@hiddenLiability.

The point of this was to not leave the thread with the idea that there can only be one @operator in a keypath.

John
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References: 
 >Proper place for functions in KVC paths? (From: "John Huss" <email@hidden>)
 >Re: Proper place for functions in KVC paths? (From: Chuck Hill <email@hidden>)
 >Re: Proper place for functions in KVC paths? (From: Lachlan Deck <email@hidden>)
 >Re: Proper place for functions in KVC paths? (From: Chuck Hill <email@hidden>)
 >Re: Proper place for functions in KVC paths? (From: Lachlan Deck <email@hidden>)



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