Functions

Dynamic typing, optionnal return value (similar to Python)
// One parameter, one return value
function discArea(r) {
  return Math.PI * r*r;
}
// Two parameters, no return value
function printMin(a,b) {
  if( a < b ) { 
    console.log(a); 
  }
  else {
    console.log(b);
  }
}
Function are simple JS variables
const F1 = function(x) { return 2*x*x+4*x+1; }
const F2 = function(x) { return -3*x*x+7*x-2; }
const currentFunction = F2;
console.log( currentFunction(8) );
Function can be defined inline with short syntax
const F = (x) => 2*x*x + 4*x +1;
console.log( F(4) );
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