Benchmark: timing 1000 iterations of glob, ordinary_mod, schwartz_mod, schwartz_orig_assign...
      glob:           148 secs ( 31.26 usr + 102.59 sys = 133.85 CPU) 
ordinary_mod:         675 secs ( 86.64 usr + 517.19 sys = 603.83 CPU) 
ordinary_orig:        825 secs (116.55 usr + 617.62 sys = 734.17 CPU) 
schwartz_mod:         151 secs ( 68.88 usr +  67.32 sys = 136.20 CPU) 
schwartz_orig:        297 secs ( 89.33 usr + 174.51 sys = 263.84 CPU) 
schwartz_orig_assign: 294 secs ( 96.68 usr + 168.76 sys = 265.44 CPU)