Patterns

1. create files for pattern matching

   $ cd
   $ mkdir patterndir
   $ cd patterndir
   $ touch a b c d e f g w x y z
   $ touch A B C D E F G W X Y Z
   $ touch aa bb cc dd ee ff gg
   $ touch AA BB CC DD EE FF GG
   $ touch ab ac ad ae ba bc bd
   $ touch aaa aaaa aaaaa
   $ touch bbb cccc ddddd
   $ touch 0 1 2 3 4 5 6 7 8 9
   $ touch 11 12 23 34 45 56 67 78 89 99
   

2. now let's try some pattern matching

   $ls
   0   23  5   78  A   CC  F   X   aaa    ad  bbb  cccc   ee  w
   1   3   56  8   AA  D   FF  Y   aaaa   ae  bc   d      f   x
   11  34  6   89  B   DD  G   Z   aaaaa  b   bd   dd     ff  y
   12  4   67  9   BB  E   GG  a   ab     ba  c    ddddd  g   z
   2   45  7   99  C   EE  W   aa  ac     bb  cc   e      gg
   $ls ?
   0  2  4  6  8  A  C  E  G  X  Z  b  d  f  w  y
   1  3  5  7  9  B  D  F  W  Y  a  c  e  g  x  z
   $ls ??
   11  23  45  67  89  AA  CC  EE  GG  ab  ad  ba  bc  cc  ee  gg
   12  34  56  78  99  BB  DD  FF  aa  ac  ae  bb  bd  dd  ff
   $ls ???
   aaa  bbb
   $ls ????
   aaaa  cccc
   $ls ?????
   aaaaa  ddddd
   $ls a?
   aa  ab  ac  ad  ae
   $ls a*
   a  aa  aaa  aaaa  aaaaa  ab  ac  ad  ae
   $ls a?*
   aa  aaa  aaaa  aaaaa  ab  ac  ad  ae
   $ls [a-c]
   a  b  c
   $ls [a-c]*
   a  aa  aaa  aaaa  aaaaa  ab  ac  ad  ae  b  ba  bb  bbb  bc  bd  c  cc  cccc
   $ls [a-c]?
   aa  ab  ac  ad  ae  ba  bb  bc  bd  cc
   $ls [!a-c]?
   11  23  45  67  89  AA  CC  EE  GG  ee  gg
   12  34  56  78  99  BB  DD  FF  dd  ff
   $ls [a-z]
   a  b  c  d  e  f  g  w  x  y  z
   $ls [0-9]
   0  1  2  3  4  5  6  7  8  9
   $ls [a-zA-z]
   A  B  C  D  E  F  G  W  X  Y  Z  a  b  c  d  e  f  g  w  x  y  z
   $ls [A-Za-z]
   A  B  C  D  E  F  G  W  X  Y  Z  a  b  c  d  e  f  g  w  x  y  z
   $ls [A-z]
   A  B  C  D  E  F  G  W  X  Y  Z  a  b  c  d  e  f  g  w  x  y  z
   $ls [a-Z]
   ls: [a-Z]: No such file or directory
   $ls [a-c]b
   ab  bb
   $ls [a-c]b*
   ab  bb  bbb