anchor.diff:  
   == OPTIONS
   
  -* *-X*, *--not* :
  -  Invert the following assertion
  +* *-0*, *--null* :
  +  Assert TOP to be null
   
  -* *-O*, *--object* :
  -  Assert TOP to be an object
  +* *-a*, *--append* :
  +  Append TOP to the end of PREV (arr.)
  +
  +* *-a*, *--append* :
  +  Set missing values from TOP (obj.) into PREV (obj.)
   
   * *-A*, *--array* :
     Assert TOP to be an array
   
  -* *-S*, *--string* :
  -  Assert TOP to be a string
  +* *-B*, *--boolean* :
  +  Assert TOP to be a boolean
   
  -* *-I*, *--integer* :
  -  Assert TOP to be an integer
  +* *-c*, *--copy* :
  +  Deep copy TOP, push onto TOP
   
  -* *-R*, *--real* :
  -  Assert TOP to be a real
  +* *-d* _NAME_, *--delete*=_NAME_ :
  +  Delete NAME from TOP (obj.)
   
  -* *-N*, *--number* :
  -  Assert TOP to be a number
  +* *-d* #, *--delete*=# :
  +  Delete # from TOP (arr.)
   
  -* *-T*, *--true* :
  -  Assert TOP to be true
  +* *-d* -#, *--delete*=-# :
  +  Delete # from the end of TOP (arr.)
  +
  +* *-e*, *--empty* :
  +  Erase all items from TOP (arr./obj.)
  +
  +* *-E*, *--equal* :
  +  Assert TOP to be equal to PREV
  +
  +* *-f* _FILE_, *--foreach*=_FILE_ :
  +  Write TOP (obj./arr.) to FILE, one line/item
  +
  +* *-f* -, *--foreach*=- :
  +  Write TOP (obj./arr.) to STDOUT, one line/item
   
   * *-F*, *--false* :
     Assert TOP to be false
   
  -* *-B*, *--boolean* :
  -  Assert TOP to be a boolean
  +* *-g* _NAME_, *--get*=_NAME_ :
  +  Get item with NAME from TOP (obj.), push to TOP
   
  -* *-0*, *--null* :
  -  Assert TOP to be null
  +* *-g* #, *--get*=# :
  +  Get # item from TOP (arr.), push to TOP
   
  -* *-E*, *--equal* :
  -  Assert TOP to be equal to PREV
  +* *-g* -#, *--get*=-# :
  +  Get # item from the end of TOP (arr.), push to TOP
   
  -* *-Q*, *--query* :
  -  Query the stack by deep copying and pushing onto TOP
  +* *-i* #, *--insert*=# :
  +  Insert TOP into PREV (arr.) at #
   
  -* *-M* #, *--move*=# :
  -  Move TOP back # places on the stack
  -
  -* *-U*, *--unwind* :
  -  Discard TOP from the stack
  +* *-I*, *--integer* :
  +  Assert TOP to be an integer
   
   * *-j* _JSON_, *--json*=_JSON_ :
     Parse JSON constant, push onto TOP
  
positive.code: * *-o* -, *--output*=- :
    Write TOP to STDOUT
  
  * *-f* _FILE_, *--foreach*=_FILE_ :
    Write TOP (obj./arr.) to FILE, one line/item
  
  * *-f* -, *--foreach*=- :
    Write TOP (obj./arr.) to STDOUT, one line/item
  
  * *-u* _FILE_, *--unquote*=_FILE_ :
    Write TOP (str.) to FILE without quotes
  
  * *-u* -, *--unquote*=- :
    Write TOP (str.) to STDOUT without quotes
  
  * *-t* #, *--truncate*=# :
    Shrink TOP (arr.) to length #
  
  * *-t* -#, *--truncate*=-# :
    Discard last # items from TOP (arr.)
  
  * *-i* #, *--insert*=# :
    Insert TOP into PREV (arr.) at #
  
  * *-a*, *--append* :
    Append TOP to the end of PREV (arr.)
  
  * *-a*, *--append* :
    Set missing values from TOP (obj.) into PREV (obj.)
  
  * *-x*, *--extend* :
    Append items from TOP to the end of PREV (arr.)
  
  * *-x*, *--extend* :
    Set all values from TOP (obj.) into PREV (obj.)
  
  * *-d* _NAME_, *--delete*=_NAME_ :
    Delete NAME from TOP (obj.)
  
  * *-d* #, *--delete*=# :
    Delete # from TOP (arr.)
  
  * *-d* -#, *--delete*=-# :
    Delete # from the end of TOP (arr.)
  
  * *-l*, *--length* :
    Push length of TOP (arr./str./obj.) to TOP
  
  * *-e*, *--empty* :
    Erase all items from TOP (arr./obj.)
  
  * *-g* _NAME_, *--get*=_NAME_ :
    Get item with NAME from TOP (obj.), push to TOP
  
  * *-g* #, *--get*=# :
    Get # item from TOP (arr.), push to TOP
  
  * *-g* -#, *--get*=-# :
    Get # item from the end of TOP (arr.), push to TOP
  
  * *-s* _NAME_, *--set*=_NAME_ :
    Sets TOP into PREV (obj.) with NAME
  
negative.code: * *-j* -, *--json*=- :
    Read from STDIN, push onto TOP
  
  * *-l*, *--length* :
    Push length of TOP (arr./str./obj.) to TOP
  
  * *-M* #, *--move*=# :
    Move TOP back # places on the stack
  
  * *-N*, *--number* :
    Assert TOP to be a number
  
  * *-o* _FILE_, *--output*=_FILE_ :
    Write TOP to FILE
  