Fix SF/2757715

	* Makefile.pamphlet (all-input): Make all-doc a requirement.
	(all-doc): Tidy.
	* doc/Makefile.in: Likewise.  Install help files.
	* doc/help: New.  Home for help files.

1 files changed, 65 insertions, 0 deletions

diff --git a/src/doc/help/undo.help b/src/doc/help/undo.help
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+Copyright The Numerical Algorithms Group Limited 1992-94. All rights reserved.
+Copyright (C) 2007-2009, Gabriel Dos Reis. All rights reserved.
+ 
+OpenAxiom Help Information.
+Section numbers refer to the on-line version of the book 
+AXIOM: The Scientific Computation System by Richard D. Jenks and Robert S. Sutor
+ 
+==============================================================================
+A.27.  )undo
+==============================================================================
+ 
+User Level Required:  interpreter
+ 
+Command Syntax: 
+ 
+  - )undo
+  - )undo integer
+  - )undo integer [option]
+  - )undo )redo
+ 
+where option is one of
+ 
+  - )after
+  - )before
+ 
+Command Description: 
+ 
+This command is used to restore the state of the user environment to an
+earlier point in the interactive session. The argument of an )undo is an
+integer which must designate some step number in the interactive session.
+ 
+)undo n
+)undo n )after
+ 
+These commands return the state of the interactive environment to that
+immediately after step n. If n is a positive number, then n refers to step
+nummber n. If n is a negative number, it refers to the nth previous command
+(that is, undoes the effects of the last -n commands).
+ 
+A )clear all resets the )undo facility. Otherwise, an )undo undoes the effect
+of )clear with options properties, value, and mode, and that of a previous
+undo. If any such system commands are given between steps n and n + 1 (n >
+0), their effect is undone for )undo m for any 0 < m <= n .
+ 
+The command )undo is equivalent to )undo -1 (it undoes the effect of the
+previous user expression). The command )undo 0 undoes any of the above system
+commands issued since the last user expression.
+ 
+)undo n )before
+ 
+This command returns the state of the interactive environment to that
+immediately before step n. Any )undo or )clear system commands given before
+step n will not be undone.
+ 
+)undo )redo
+ 
+This command reads the file redo.input. created by the last )undo command.
+This file consists of all user input lines, excluding those backtracked over
+due to a previous )undo.
+ 
+Also See: 
+o )history
+The command )history )write will eliminate the ``undone'' command lines of
+your program.
+