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Paradigm multi-paradigm, functional, object-oriented
Designed by Jeremy Ashkenas, Satoshi Murakami, George Zahariev
Developer Jeremy Ashkenas, Satoshi Murakami, George Zahariev
First appeared 2011; 6 years ago (2011)
Stable release
LiveScript 1.5.0 / 15 May 2016; 17 months ago (2016-05-15)[1]
Typing discipline dynamic, weak
OS Cross-platform
License MIT
Filename extensions .ls
Influenced by
JavaScript, Haskell, CoffeeScript, F#

LiveScript is a functional language that compiles to JavaScript. It was created by Jeremy Ashkenas—the creator of CoffeeScript—along with Satoshi Muramaki, George Zahariev, and many others.[2] Notably, LiveScript was briefly the name of JavaScript in 1990s.[3]


LiveScript is an indirect descendant of and partly compatible with CoffeeScript.[4] The following is a fully Coffeescript-compatible hello-world example of LiveScript syntax.

hello = ->
  console.log 'hello, world!'

While calling a function can be done with empty parens, hello(), LiveScript treats the exclamation mark as a single-character shorthand for function calls with zero arguments: hello!

LiveScript introduces a number of other incompatible idioms:

Name mangling[edit]

At compile time, the LiveScript parser implicitly converts kebab case (dashed variables and function names) to camelcase.

hello-world = ->
  console.log 'Hello, World!'

With this definition, both the following calls are valid. However, calling using the same dashed syntax is recommended.


This does not preclude developers from using camelcase explicitly or using snakecase. Dashed naming is however, common in idiomatic LiveScript[5]


Like a number of other functional programming languages such as F# and Elixir, LiveScript supports the pipe operator, |> which passes the result of the expression on the left of the operator as an argument to the expression on the right of it. Note that in F# the argument passed is the last argument, while in Elixir it is the first.

"hello!" |> capitalize |> console.log
# > Hello!

Operators as functions[edit]

When parenthesized, operators such as not or + can be included in pipelines or called as if they were functions.

111 |> (+) 222
# > 333

(+) 1 2
# > 3


  1. ^ "LiveScript Releases". Retrieved 3 March 2017. 
  2. ^ "LiveScript contributors page". Retrieved 20 June 2015. 
  3. ^ "W3 Web Education Community Group". Retrieved 20 June 2015. 
  4. ^
  5. ^

External links[edit]