Pebble Graphics Development - Function Interface

The basic idea is you can create "scopes" or anonymous functions which are containers you can place a computation inside of that has its own symbol table. These can then be placed inside symbol tables themselves to name the function.

0:00 - An empty scope with a single variable 'z' in its symbol table
0:12 - Creating the body of the function as 'z + 5'
0:25 - Naming the new function 'x' by putting it in a symbol table, this changes existing instances of 'x' by adding the function's symbol table
0:35 - Changing what 'x' is bound to updates the instances of 'x' to not have a symbol table
0:38 - Updating the function body to be 'y + 5' and reassigning it to 'x'