Declare a dictionary as mixted list across multiple lines

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1

Hello, at my previous job I remember I got a nice trick to declare a dictionary over several lines, this was nice as it was much more readable.
Something like

d: listToDict[ (`key1; value1) \

(`key2; object2) \

(`key3; value3) \

(`key4; object4) ];

So there were a trick on how to make a list of list as a dictionary and also how to use multiline commands.

I know I could do 

d:(key1key2)!(`;0N);

d[`key1]:value1

…

But it is not what I want.

Would someone know this trick ?

2

q)(!). flip ((a;1);(b;2))
a| 1
b| 2

3

Hi

The trick is usually to declare it as a list of lists, where each inner list is (key;value).  Then flip it and use ! . to turn the resulting 2 lists into a dictionary.  Something like 

(!) . flip

((`a;1);

 (`b;2);

 (`c;3))

Thanks 

Jonny

4

(!/) is nicer as (!/)() is ()
which is useful as a default

another option is just to use one level of nesting

and create the second programatically

for convenience (it will be somewhat slower)

q)(!/)flip 2 cut (a;1; b;2; `c;3)

Cheers,

   Attila

5

>> (!/) is nicer as (!/)() is () which is useful as a default
depends on your interpretation of nice. i’d prefer to see an exception raised during the creation of a dictionary rather than later when trying to do a lookup. but each to their own.