7stud
Updating a map's values that are lists
What is the Elixir equivalent to Ruby’s Hash.new where you can specify a block that returns an empty list when you access a non-existent key (or Perl’s autovivification feature)?
The idea is that when you access a key in a Map that doesn’t exist you get back an empty list, which you can then append values to. And, if the key does exist, then you get back a non-empty list, which you can also append values to.
Also, why is it that the editor for this forum has a textbox that says “choose optional tags for this topic”, yet when I submit my question, I get an alert that says “You must choose at least 1 tag”, yet none of the tags are relevant to my question?
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sribe
Elixir is not Perl. The phrase “if you treat a value returned by a key as a list” makes no sense in the Elixir context–you’re basically saying “if you expect of type XXX and you get nil, then automagically create an XXX and substitute it”, and that is exactly the kind of implicit magic that Elixir tries to avoid, by design.
AstonJ
We generally don’t use ‘elixir’ as a tag since pretty much everything is related to Elixir on this forum 
(and so I’ve made it a staff only tag)
I’ve added maps and lists as tags as they seem most relevant 
sribe
Don’t confuse syntactic sugar and implicit magic–the examples you post are all completely explicit.
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