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  • nice toys like list comprehensions


  • adds a compilation step
  • no native browser support yet (source maps can be used to get CoffeeScript visible in the debugger, but you can’t type CoffeeScript in the browser console)
  • language designed for writability but not readability (compare that with Knuth’s proposal: "Let us change our traditional attitude to the construction of programs. Instead of imagining that our main task is to instruct a computer what to to, let us concentrate rather on explaining to human beings what we want a computer to do."):
    • multiple ways to do things
    • implicit considered better than explicit; parentheses, braces, commas and other elements are (often) optional

See also