\ SAVE-INPUT and RESTORE-INPUT\\ This code is part of pForth.\\ The pForth software code is dedicated to the public domain,\ and any third party may reproduce, distribute and modify\ the pForth software code or any derivative works thereof\ without any compensation or license.  The pForth software\ code is provided on an "as is" basis without any warranty\ of any kind, including, without limitation, the implied\ warranties of merchantability and fitness for a particular\ purpose and their equivalents under the laws of any jurisdiction. anew task-save-input.fth private{ : SAVE-BUFFER ( -- column source-id 2 ) >in @ source-id 2 ; \ Restore >IN from COLUMN unless COLUMN is too large.  Valid values\ for COLUMN are from 0 to (including) the length of SOURCE plus one.: RESTORE-COLUMN ( column -- flag )    source nip 1+ over u<    IF   drop  true    ELSE >in ! false    THEN; \ Return the file-position of the beginning of the current line in\ file SOURCE-ID.  Assume that the current line is stored in SOURCE\ and that the current file-position is at an end-of-line (or\ end-of-file).: LINE-START-POSITION ( -- ud )    source-id file-position throw    \ unless at end-of-file, subtract newline    source-id file-size throw 2over d= 0= IF 1 s>d d- THEN    \ subtract line length    source nip s>d d-; : SAVE-FILE ( column line filepos:ud source-id 5 -- )    >in @    source-line-number@    line-start-position    source-id    5; : RESTORE-FILE ( column line filepos:ud -- flag )    source-id reposition-file  IF 2drop true EXIT THEN    refill                     0= IF 2drop true EXIT THEN    source-line-number!    restore-column; : NDROP ( n*x n -- ) 0 ?DO drop LOOP ; }private \ Source      Stack\ EVALUATE    >IN  SourceID=(-1)  2\ keyboard    >IN  SourceID=(0)   2\ file        >IN  lineNumber filePos  SourceID=(fileID) 5: SAVE-INPUT ( -- column {line filepos}? source-id n )    source-id CASE	-1 OF save-buffer ENDOF	0  OF save-buffer ENDOF	drop save-file EXIT    ENDCASE; : RESTORE-INPUT ( column {line filepos}? source-id n -- flag )    over source-id <> IF ndrop true EXIT THEN    drop    CASE	-1 OF restore-column ENDOF	0  OF restore-column ENDOF	drop restore-file EXIT    ENDCASE; privatize