JavaScript Pure

pure.js

const { log } = console;

/*
* Aritmética: equal, max, min, negative, positive, reverseSign, opositeSigns
* swap, def, undef, plus, minus, sum
*/

const equal = function( x, y ) {
  return ( x === y );
};

const max = function( x, y ) {
  return ( x > y ) && x || y;
};

const min = function( x, y ) {
  return ( x < y ) && x || y;
};

const negative = function( n ) {
   return ( n < 0 ); 
};

const positive = function( n ) {
  return !negative( n );
};

const reverseSign = function( n ) {
  return ~n + 1;
};

const opositeSigns = function( x, y ) {
  return ( ( x ^ y ) < 0 );
};

const swap = function( [ x, y ] ) {
  return [ y, x ];
};

const plus = function( x ) {
  return x + 1;
}

const minus = function( x ) {
  return x - 1;
}

const sum = function( x, y ) {
  return x + y;
}

/*
* Tipos: def, undef
*/

const def = function( x ) {
  return typeof x !== 'undefined';
}

const undef = function( x ) {
  return !def( x );
}

/*
* Vetores: addV, clone, deletee, head, tail, pop, push, shift
* unshift, sort, splice, uniq
*/

const addA = function( [ x, y, ...ys ] ) {
  return undef( x ) 
    ? 0 : undef( y )
    ? x : equal( ys.length, 0 )
    ? sum( x, y ) : sum( x, addA( [ y, ...ys ] ) );
};

const head = function( [ x, ...xs ] ) {
  return x;
};

const tail = function( [ , ...xs ] ) {
  return xs;
}

const clone = function( x ) {
  return [ ...x ];
};

const deletee = function( i ) {
  return function( x ) { 
    return [ ...x.slice( 0, i ), ...x.slice( i + 1 ) ];
  };
};

const pop = function( x ) {
  return x.slice( 0, -1 );
};

const push = function( y ) {
  return function( x ) {
    return [ ...x, y ];
  };
};

const shift = function( x ) {
  return x.slice( 1 );
};

const unshift = function( y ) {
  return function( y ) {
    return [ y, ...x ]
  };
};

const sort = function( f ) {
  return function( x ) {
    return [ ...x ].sort( f );
  }
}

const splice = function( s, c, ...y ) {
  return function( x ) {
    return [ ...x.slice( 0, s ), ...y, ...x.slice( s + c ) ]
  };
};

const uniq = function( xs ) {
  return [ ...new Set( xs ) ];
}