CoffeeScript

NanoBricks uses the CoffeeScript programming language for scripting; in many places within NanoBricks, you can write little snippets of CoffeeScript to automate repetitive tasks. Coffeescript looks a lot like Python or Ruby, but runs in your browser. Check out http://coffeescript.org/ for lots more detail.

Operators

Standard mathematical operators are available:

• Arithmetic: +, -, *, /, % (Modulo/remainder), ** (Exponentiation), // (Integer division/floor), %% (Mathematical modulo)
• Comparison and Logic: <, >, <=, >=, is (==), isnt (!=), and, or, not in

Note that true/yes/on are the same, and false/no/off are the same.

Lists

Make lists with square brackets []:

my_list = [item1, item2, item3]

Easily make ranges using ... (exclusive)

range = [0...5] # = [0, 1, 2, 3, 4]

or .. (inclusive)

range = [0..5] # = [0, 1, 2, 3, 4, 5]

Test for list or range membership with in:

2 in [0..5] # true
4 in [0, 2, 6, 16] # false

Normal arithmetic operators (+, -, is, etc.) don't work on lists; instead, NanoBricks provides some small functions which you can use for easy element-wise arithmetic.

• Arithmetic: add, subtract, muliply, divide (take two arrays, return new array). Example:

    add [1, 2, 3], [5, 6, 7] # [6, 8, 10]
    div [2, 4, 8], [2, 2, 2] # [1, 2, 3]
  

• Comparison and logic: equals (eq), less, greater, leq, geq, and sum (take two arrays, return scalar). Example:

    eq [1, 2, 3], [5, 6, 7] # false
    less [1, 2, 3], [1, 2, 4] # true
  

For more complicated operations, you can use a comprehension:

a = [4, 6, 13]
b = [1, 6, 2]
(Math.sqrt a[i] ** b[i]) for x,i in a

Loops

Loop forever with loop.

Loop over a collection or range with for...in:

for i in [0..5]
    action

You can get a list of results as well:

items = (i+1 for i in [0..5]) # [1, 2, 3, 4, 5, 6]

Filter the list with when:

items = (i+1 for i in [0..5] when i isnt 3) # [1, 2, 3, 5, 6]

Objects

Make objects with curly braces: {}:

my_object = { foo: 'bar', baz: 'bat'}
my_object.foo = 'new value'

Or implicitly, using indentation:

my_object = 
    foo: 'bar'
    baz: 'bat'

Test for object membership using of:

'foo' of { foo: 1, bar: 2 } # true

Conditions

Write conditions using if and else; indent the actions:

if condition 1
     action 1
else if condition 2
     action 2
else
     action 3

Use then to write actions inline with conditions: if conditon then action 1 else action 2

unless is the opposite of if: unless conditon then action 1 else action 2

You can also use conditionals as expressions:

color = if x > 5 then 0xff0000 else 0x000000

Functions

Call functions by writing the name, then the arguments:

my_func arg1, arg2

You can use parenthesis to call functions with no arguments, or to make things clearer:

my_func()
my_func_1 my_func_2(arg1,arg2)

You can pass a list of arguments using the splat (...):

list_of_args = [arg1, arg2, arg3]
my_func list_of_args... # the same as my_func arg1, arg2, arg3

Define functions with an arrow ->. Use indentation for a multi-line body. The last value will be returned:

my_func = (arg1, arg2) ->
    ...
     return expression

my_short_function = (arg1, arg2) -> return expression

You can still use the return keyword if you want to return prematurely.