map Include in Julia

In Julia, you can check if a hash includes a key by using the in keyword or the haskey() function.

Here's an example of using the in keyword to check if a key exists in a hash:

myhash = Dict("a" => 1, "b" => 2, "c" => 3)
if "a" in keys(myhash)

    println("Key 'a' exists in myhash")

else

    println("Key 'a' does not exist in myhash")

end

Output:

Key 'a' exists in myhash

Here's another example using the haskey() function:

myhash = Dict("a" => 1, "b" => 2, "c" => 3)
if haskey(myhash, "d")

    println("Key 'd' exists in myhash")

else

    println("Key 'd' does not exist in myhash")

end

Output:

Key 'd' does not exist in myhash

In both examples, we create a hash myhash with key-value pairs, and then we check if the key exists in the hash using in or haskey(). If the key exists, we print a message stating that the key exists in the hash, otherwise we print a message stating that the key does not exist in the hash.