Initial Commit

Code/6.dicts.jl

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+
+# Dicts (dictionaries/maps) are not as simple as in python, resembling
+# more the way modern c++ does it
+
+# Dicts are usually created from an array of "Pair" types (First => Last)
+# The type of the dict keys and values are automatically infered.
+d = Dict([
+    "foo" => 3,
+    "bar" => 7
+])
+display(d)
+
+# A dict can also be initialized as an array of two tuples. This works
+# identically to the example above
+d = Dict([
+    ("foo", 2.71),
+    ("bar", 3.14)
+])
+display(d)
+
+# Values can be pushed to the dict similarly to an array.
+# Keep in mind that creating an empty dict like this gives the type
+# Dict{Any, Any} which might be somewhat slower because of having
+# to work for general types
+d = Dict()
+push!(d, "foo" => 1//2)
+push!(d, "bar" => 22//7)
+display(d)
+
+# The problem above can be mitigated by infering the types manually
+d = Dict{String, Rational{Int}}()
+push!(d, "foo" => 1//2)
+push!(d, "bar" => 22//7)
+display(d)
+
+# A key can be deleted from a dict with delete!()
+delete!(d, "foo")
+display(d)
+
+# To check if a certain key exists in the dict, the haskey function is used
+println(haskey(d, "foo")) # false
+println(haskey(d, "bar")) # true
+
+# Indexing a dict is done with brackets like for any array
+println(d["bar"])