Benchmarks

# npm run bench
# on windows 10 - i7 - 64 bits
# es2015 module


on                    x          380,521 ops/sec ±1.15% (86 runs sampled)
once                  x          227,738 ops/sec ±4.36% (72 runs sampled)
off - single          x          313,417 ops/sec ±11.55% (82 runs sampled)
off - array           x          379,185 ops/sec ±0.42% (92 runs sampled)
emit - on             x          370,083 ops/sec ±0.91% (90 runs sampled)
emit - on - params    x          370,337 ops/sec ±1.22% (92 runs sampled)
emit - once           x          329,562 ops/sec ±7.65% (84 runs sampled)
emit - once - params  x          388,217 ops/sec ±1.29% (88 runs sampled)