anchor.diff:  
   * *-s* -#, *--set*=-# :
     Sets TOP into PREV (obj.) at # from the end
  +
  +* *-S*, *--string* :
  +  Assert TOP to be a string
  +
  +* *-t* #, *--truncate*=# :
  +  Shrink TOP (arr.) to length #
  +
  +* *-t* -#, *--truncate*=-# :
  +  Discard last # items from TOP (arr.)
  +
  +* *-T*, *--true* :
  +  Assert TOP to be true
  +
  +* *-u* _FILE_, *--unquote*=_FILE_ :
  +  Write TOP (str.) to FILE without quotes
  +
  +* *-u* -, *--unquote*=- :
  +  Write TOP (str.) to STDOUT without quotes
  +
  +* *-U*, *--unwind* :
  +  Discard TOP from the stack
  +
  +* *-x*, *--extend* :
  +  Append items from TOP to the end of PREV (arr.)
  +
  +* *-x*, *--extend* :
  +  Set all values from TOP (obj.) into PREV (obj.)
  +
  +* *-X*, *--not* :
  +  Invert the following assertion
   
   * *-y*, *--b64load* :
     URL-safe Base64 decode TOP (str.), push onto TOP
  
positive.code: * *-j* -, *--json*=- :
    Read from STDIN, push onto TOP
  
  * *-c*, *--copy* :
    Deep copy TOP, push onto TOP
  
  * *-q* _STR_, *--quote*=_STR_ :
    Convert STR to a string, push onto TOP
  
  * *-o* _FILE_, *--output*=_FILE_ :
    Write TOP to FILE
  
negative.code: * *-o* -, *--output*=- :
    Write TOP to STDOUT
  
  * *-O*, *--object* :
    Assert TOP to be an object
  
  * *-q* _STR_, *--quote*=_STR_ :
    Convert STR to a string, push onto TOP
  
  * *-Q*, *--query* :
    Query the stack by deep copying and pushing onto TOP
  
  * *-R*, *--real* :
    Assert TOP to be a real
  
  * *-s* _NAME_, *--set*=_NAME_ :
    Sets TOP into PREV (obj.) with NAME
  