RazgrizHsu
How to add key/value element to List with variable
we can create a list like this
list = [ a: 1, b: 2, c: 3 ]
but i can’t found api to add element with key to list?
list = []
key = :a
value = 1
#wrong ( * (SyntaxError) iex:4: syntax error before: '=>' )
list = list ++ [ key => value ]
anyone know how to do that?
thank you 
Marked As Solved
LostKobrakai
Keyword lists are syntax sugar over a list of tuples, which are strictly {atom(), term()}. So you can do list ++ [{key, value}].
Also Liked
lpil
As an extra tip, list ++ [{key, value}] is quite slow as you need to traverse the entire list to add [{key, value}] to the end.
As a rule of thumb you should add elements to the front of the list, which happens in constant time [{key, value} | list]
NobbZ
hauleth
Which is slower than [{key, value} | list] as this need to traverse all list and remove duplicates.
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