--- freem/doc/freem.texi	2025/05/02 20:01:12	1.38
+++ freem/doc/freem.texi	2025/05/04 13:46:10	1.41
@@ -7,6 +7,7 @@
 This manual is for FreeM, (version 0.64.0-rc1), which is a free software@footnote{FreeM subscribes to the software licensing philosophy described in @emph{Free Software, Free Society:
 Selected Essays of Richard M. Stallman}.} implementation of the M programming language.
 
+Print-optimized versions of this book are typeset in @emph{Computer Modern} by the author using the @emph{GNU Texinfo} tools.
 
 Copyright @copyright{} 2014-2025 Coherent Logic Development LLC
 
@@ -44,6 +45,7 @@ This is the official manual for the Free
 @menu
 * Introduction::                        About the FreeM Project, its history, and its goals.
 * Document Conventions::                Conventions used in this manual.
+* A Note on Standards::                 FreeM positioning regarding the M Development Committee.
 * FreeM Invocation::                    How to invoke FreeM from the command line.
 * The FreeM Environment Daemon::        Managing shared resources in the FreeM environment.
 * The FreeM Direct-Mode Environment::   Executing M programs interactively.
@@ -117,6 +119,8 @@ When GT.M was open-sourced in late 1999,
 
 In February of 2020, work began in earnest to build a development and support infrastructure for FreeM and begin the careful process of refining it into a more stable and robust application.
 
+For more information on FreeM history, see @code{@emph{$PREFIX}/share/freem/doc/freem_history.*} (distributed in PostScript, PDF, and plain text formats).
+
 @section Production Readiness
 
 FreeM is not yet production-ready. There are several show-stopping bugs that preclude a general release for public use:
@@ -276,6 +280,20 @@ Refers to the name of an M structured sy
 Refers to a truth-valued expression.
 @end table
 
+@node A Note on Standards
+@chapter A Note on Standards
+@cindex MDC
+@cindex M Development Committee
+@cindex ANSI X11.1
+@cindex standards, ANSI
+@cindex standards, MDC
+
+FreeM attempts to implement as many features as possible from the M Development Committee's unpublished @emph{Millennium Draft Standard}, as well as its predecessors.
+
+The maintainer of FreeM (who is also the author of this book) is largely in favor of standardization efforts, and hopes that the MDC will resume activities, and will happily participate if it does so in an open, public, transparent, and democratic manner. Until then, however, FreeM will attempt to improve the M language, in cooperation with other free software M implementers where possible. Any breaking changes introduced in future MDC releases of the @emph{Standard} (such as the rumored @emph{M5}) which prove incompatible with FreeM will be handled via the @code{$DIALECT} special variable (to be changed to @code{$ZDIALECT} in a coming release).
+
+The conformance document required per the @emph{Standard} should be installed as a @code{man} page on any computer system where FreeM is made available. Simply type @code{man freem_conformance} to access.
+
 @node FreeM Invocation
 @chapter FreeM Invocation
 @cindex invocation, command-line
@@ -2404,7 +2422,7 @@ ELSE[@emph{:postcondition}]
 @quotation
 @emph{Non-Standard Behavior}
 
-FreeM allows a @emph{postcondition} on @code{ELSE}. While explicitly forbidden in the @emph{standard}--and for good reason--it was decided that FreeM should allow postconditions everywhere, both for the sake of foolish consistency (the likes of which Emerson warned against), and for the benefit of entrants to a hypothetical future obfuscated M contest, and those with a Machiavellian predisposition to wicked perversions and undue cleverness.
+FreeM allows a @emph{postcondition} on @code{ELSE}. While explicitly forbidden in the @emph{Standard}, it was decided that FreeM should allow postconditions everywhere, both for the sake of foolish consistency (the likes of which Emerson warned against), and for the benefit of entrants to a hypothetical future obfuscated M contest, and those with a Machiavellian predisposition to wicked perversions and undue cleverness.
 
 Using postconditions on @code{ELSE} should be strictly avoided in production code, as they have no practical use, and may contribute to technical debt, hardening of the arteries, hobgoblins, a small mind, a surfeit of logic, climate change, @emph{Daily WTF} rants, or the meltdown of global financial markets.
 @end quotation
@@ -2559,11 +2577,22 @@ IF[@emph{:postcondition}] @emph{tvexpr}[
 
 In its argumentless form, allows the remainder of the line of code following @code{IF} to execute only if @code{$TEST} evaluates to @emph{1}, provided the optional @emph{postcondition} evaluates to @emph{true} or is omitted.
 
+
 @emph{Syntax}
 @example
-IF[@emph{:postcondition}]
+IF[@emph{:postcondition}]  @emph{command...}
 @end example
 
+@cartouche
+@quotation
+@emph{Style Recommendation}
+
+In the interest of readability and maintainability, we recommend avoiding the argumentless form of @code{IF} in new code. It is an obsolete relic of an era when routine sizes were severely limited, and can be difficult to spot, as the use of whitespace (@code{IF  @emph{command}}) makes the intent of its use non-obvious at a glance. It is also far too easy to inadvertently delete the extra space, leading to program errors easily avoided otherwise.
+
+We recommend explicitly checking the value of @code{$TEST} instead, as in @code{IF $TEST @emph{command}} or @code{@emph{command}:$TEST ...}, as this makes the intent immediately clear both to M newcomers and seasoned experts, and sacrifices nothing of value, even on the oldest computer systems where FreeM can be used today.
+@end quotation
+@end cartouche
+
 @node JOB
 @section JOB
 @cindex JOB
@@ -4672,7 +4701,7 @@ Transaction processing allows applicatio
 @section Transaction Processing
 @cindex transaction processing
 
-FreeM implements a significant subset of the transaction processing features from @emph{ANSI X11.1-1995}. This allows a series of global operations to be conducted all at once, either in batch mode (where concurrency is not disturbed), or in serial mode (where writes are guaranteed to be atomic, consistent, isolated, and durable).
+FreeM implements a significant subset of the transaction processing features from @emph{ANSI X11.1-1995}. This allows a series of global operations to be conducted all at once, either in batch mode (where concurrent operation is not interrupted until the last possible moment), or in serial mode (where writes are guaranteed to be atomic, consistent, isolated, and durable).
 
 @subsection Theory of Operation
 
@@ -4751,6 +4780,13 @@ The effect of this is that the operation
 @cindex variables, local
 @cindex local variables
 
+@menu
+* Local Variables Overview::            The basics of locals.
+* Creating Local Variables::            Creating locals with SET.
+* Removing Local Variables::            Removing locals with KILL.
+@end menu
+
+@node Local Variables Overview
 @section Local Variables Overview
 
 FreeM @emph{local variables} have the same data structure as global variables, but are scoped to a single FreeM process, and stored in memory.
@@ -4808,6 +4844,54 @@ By default, FreeM local variables and th
 
 M provides the @code{NEW} command to work around these issues. When @code{NEW} is called with a local variable as its argument, FreeM will scope the variable to the process stack frame in which the @code{NEW} command occured. When exiting the stack frame (i.e. with the @code{QUIT} command), FreeM will restore the variable to its value prior to being @code{NEW}ed.
 
+@emph{Example}
+
+@example
+MYRTN ;
+  S J=1 ; set local variable J to 1
+  W J,! ; this will output "1"
+  D X   ; execute subroutine X
+  W J,! ; this will output "1", as the value of J was restored
+  Q
+  ;;
+X ;
+  N J   ; stack J
+  S J=6 ; set its value to 6
+  W J,! ; this will output "6"
+  Q     ; quit from the subroutine, destroying its stack frame
+  ;;
+@end example
+
+@section Scoping Considerations for $TEST
+
+In M, the truth value of comparisons, logic operations, and certain forms of @code{LOCK} is stored in the @code{$TEST} intrinsic special variable, which follows the same rules as any M local variable.
+
+This is probably the most significant design flaw of the language, as the side effects of logic on @code{$TEST} lead to incredibly difficult bugs. However, M allows @code{$TEST} to be @code{NEW}ed, and FreeM provides the @code{THEN} command@footnote{From MDC Type A extension X11/1998-31} to help in the case of conditionals. @code{THEN} stacks @code{$TEST} to the end of the line.
+
+When writing new M code in FreeM, we strongly suggest using @code{THEN} as follows:
+
+@example
+MYRTN ;
+  IF MYVAR=1 THEN DO SUBRT
+@end example
+
+This is instead of the traditional form:
+
+@example
+MYRTN ;
+  IF MYVAR=1 DO SUBR
+@end example
+
+@cartouche
+@quotation
+@emph{Style Recommendation}
+
+Note that @code{THEN} is not in any currently published version of the @emph{Standard}, but is part of MDC Type A extension X11/1998-31. However, we recommend using @code{THEN} instead of favoring portability, as there is no defensible reason for this incredibly simple feature @emph{not} to be ubiquitous.
+
+If you use other M implementations, you should bug the implementers to implement @code{THEN}, as it at least partially mitigates an inexcusable flaw in the design of M.
+@end quotation
+@end cartouche
+
 @node Decision Constructs
 @chapter Decision Constructs
 @cindex decision constructs
@@ -4866,6 +4950,8 @@ M provides the @code{NEW} command to wor
 * Class Overview::                  Class basics.
 * Constructors::                    Managing object creation.
 * Destructors::                     Cleaning up.
+* Inheritance::                     Deriving classes from other classes.
+* Methods::                         Adding code to classes.
 * Runtime Polymorphism::            Selecting methods at runtime.
 @end menu