bracket spacing threw unexpected error in function invocation

[sourcevault]

a = 1
b = 2

f = (x,y) -> x + y

f (a,b) # throws error :(

I was quite surprised that this caused parse error :|

Function {
  message: 'Parse error on line 1: Unexpected \',\'',
  hash:
   { text: undefined,
     token: ',',
     line: 0,
     loc: { first_line: 0, first_column: 3, last_line: 0, last_column: 4 },
     expected:
      [ '\'BIOP\'',
        '\')\'',
        '\'BIOPR\'',
        '\'BACKTICK\'',
        '\'NEWLINE\'',
        '\'INDENT\'',
        '\'IMPORT\'',
        '\'+-\'',
        '\'COMPARE\'',
        '\'LOGIC\'',
        '\'MATH\'',
        '\'POWER\'',
        '\'SHIFT\'',
        '\'BITWISE\'',
        '\'CONCAT\'',
        '\'COMPOSE\'',
        '\'RELATION\'',
        '\'PIPE\'',
        '\'BACKPIPE\'',
        '\'POST_IF\'' ] } }

[vendethiel]

That's correct. This is an error. LiveScript has no tuples.

[sourcevault]

I am trying to do a normal function call like so :

f a,b # no error 

[rhendric]

Welcome to LiveScript! It's true, f (a, b) is not valid and is not intended to be so. LiveScript is a very whitespace-sensitive language. For example, there is a big difference between a[b, c] and a [b, c]—the former will compile to [a[b], a[c]], while the latter will compile to a([b, c]). By analogy, f (a, b) would mean to apply f to whatever (a, b) means, but as ven observes, the expression (a, b) doesn't mean anything in LiveScript, so this is an error, whereas f(a, b) is valid (as is f a, b, as you observe).