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The any permission

⚠️ DADA DOESN'T REALLY EXIST. ⚠️

See the About page for more information. Also, you have to pretend that all the code examples are editable and runnable, with live IDE tooltips and so forth. =)

Rather than labeling variables as my or our, you can also use the any keyword. This will permit the variable to store an object with any permission. When using any, the give and share keywords allow you to control the ownership:

class Point(our x, our y)

# The point is `my` when first created
any my_p = Point(22, 44)

# You can `give` it to another variable
any my_p_now = my_p.give

# You can `share` it
any our_p = my_p_now.share

# Giving a shared thing is a copy
any also_our_p = our_p.give

# So is sharing
any and_our_p_too = our_p.share

Using any to operate on multiple permissions with one function​

The any permission is useful if you want to have functions that operate over multiple permissions. Consider the function give_a:

class Pair(my a, my b)

fn give_a(any pair) -> {
    pair.a.give
}

If give_a is called on a my object, it will return a my object, as shown here:

# class Pair(my a, my b)
# 
# fn give_a(any pair) -> {
#     pair.a.give
# }

class Widget(our name)
my my_pair = Pair(Widget("a"), Widget("b"))
my my_widget = give_a(my_pair)
print(my_widget).await                         # Prints 'Widget("a")'
print(my_pair).await                           # Error, my_pair has been given away

But if give_a is called on an our object, it will return an our object:

# class Pair(my a, my b)
# 
# fn give_a(any pair) -> {
#     pair.a.give
# }

class Widget(our name)
our our_pair = Pair(Widget("a"), Widget("b"))
our our_widget = give_a(our_pair)
print(our_widget).await                         # Prints 'Widget("a")'
print(our_pair).await                           # Prints 'Pair(Widget("a"), Widget("b"))'

A hint of what's to come: generic functions​

In Typed Dada, any functions become a shorthand for generic functions.