--- freem/doc/freem.texi 2025/05/01 21:02:31 1.35 +++ freem/doc/freem.texi 2025/05/02 14:35:40 1.36 @@ -4,7 +4,8 @@ @settitle The FreeM Manual @copying -This manual is for FreeM, (version 0.64.0-rc1), which is a free and open-source implementation of the M programming language. +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. Copyright @copyright{} 2014-2025 Coherent Logic Development LLC @@ -42,9 +43,11 @@ 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. * 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. +* Debugging:: The program development cycle of FreeM. * Directives:: Per-Routine Language Directives. * Intrinsic Special Variables:: Intrinsic Special Variables. @@ -91,7 +94,6 @@ This is the official manual for the Free * Interrupt Handling:: How FreeM handles interrupts. * Error Processing:: How to handle errors in M program code. * FreeM Error Codes:: Explanations of each FreeM error code. -* Debugging:: The program development cycle of FreeM. * System Configuration:: Configuring your FreeM installation. * Accessing FreeM from C Programs:: How to use the mlib interface. @@ -109,11 +111,11 @@ This is the official manual for the Free @node Introduction @unnumbered Introduction -FreeM started its life as @emph{FreeMUMPS}, written for MS-DOS and ported to SCO UNIX by a mysterious individual going by the name of "Shalom ha-Ashkenaz". It was released to MUG Deutschland in 1998. In 1999, Ronald L. Fox ported FreeM to the Red Hat Linux 5 of the GNU/Linux operating system. Thereafter, maintenance was taken over by the Generic Universal M Project, which changed its name first to Public Standard MUMPS and then by popular request to FreeM. +FreeM started its life as @emph{FreeMUMPS}, written for MS-DOS and ported to SCO UNIX by a mysterious individual going by the name of "Shalom ha-Ashkenaz". It was released to MUG Deutschland in 1998. In 1999, Ronald L. Fox ported FreeM to the Red Hat Linux 5 distribution of the GNU/Linux operating system. Thereafter, maintenance was taken over by the Generic Universal M Project, which changed its name first to Public Standard MUMPS and then by popular request to FreeM. When GT.M was open-sourced in late 1999, FreeM and GUMP were essentially abandoned. L.D. Landis, the owner of the original GUMP SourceForge project, and one of FreeM's significant contributors, passed maintenance of FreeM and ownership of its SourceForge project to Serena Willis in 2014. At this point, FreeM would not compile or run on modern Linux systems, so steps were taken to remedy the most pressing issues in the codebase. Limitations on the terminal size (previously hard-coded to 80x25) were lifted, and new @code{$VIEW} functions were added to retrieve the terminal size information. @code{$X} and @code{$Y} intrinsic special variables were updated to support arbitrary terminal sizes, and FreeM was once again able to build and run. -In February of 2020, work began in earnest to build a development and support infrastructure for FreeM and begin the careful process of refining it into a more stable and robust product. +In February of 2020, work began in earnest to build a development and support infrastructure for FreeM and begin the careful process of refining it into a more stable and robust application. @section Production Readiness @@ -224,6 +226,48 @@ Serena Willis (Current Maintainer and Pr Steve Zeck (Code) @end itemize + +@node Document Conventions +@chapter Document Conventions +@cindex document conventions +@cindex conventions + +@section Formatting Conventions + +This manual uses the following formatting conventions: +@itemize +@item Code examples, filesystem paths, and commands are presented in @code{monospace} +@item Placeholders where the reader is expected to supply a replacement value are presented in @code{@emph{monospace italics}}, and depending on context, may be surrounded by angle brackets +@item New terminology is introduced in @emph{proportional italics} +@end itemize + +@section Definitions + +FreeM uses abbreviations for common language elements: + +@table @asis +@item @emph{$PREFIX} +Refers to the base filesystem location within which FreeM is installed. For most distribution methods of FreeM, @emph{$PREFIX} represents either @code{/} or @code{/usr/local}. +@item @emph{expr} +Refers to any expression. Often presented in the format @emph{expr V }, where @emph{V} means @emph{giving}; e.g., @emph{expr V lvn} means @emph{expression giving local variable name}. +@item @emph{glvn} +Refers to the name of an M global, local, or structured system variable. +@item @emph{gvn} +Refers to the name of an M global variable. +@item @emph{intexpr} +Refers to an integer expression. +@item @emph{ISV}, @emph{isv} +Refers to an M intrinsic special variable; @code{$JOB} and @code{$IO} are examples of ISVs. +@item @emph{L} +Indicates a @emph{list} of the following item, e.g., @emph{L gvn} means @emph{list of global variable names}. +@item @emph{lvn} +Refers to the name of an M local variable. +@item @emph{ssvn} +Refers to the name of an M structured system variable. +@item @emph{tvexpr} +Refers to a truth-valued expression. +@end table + @node FreeM Invocation @chapter FreeM Invocation @cindex invocation, command-line @@ -240,7 +284,7 @@ When @code{-r} or @code{--routine} are p @section %SYSINIT Routine -The @code{%SYSINIT} routine runs every time a FreeM interpreter process starts. This routine defines some useful constants, enables handling of @code{TRIGGER} events, and handles the execution of code passed via the @code{-x\--execute} or routines passed via @code{-r|--routine}. +The @code{%SYSINIT} routine runs every time a FreeM interpreter process starts. This routine defines some useful constants, enables handling of @code{TRIGGER} events, and handles the execution of code passed via the @code{-x|--execute} or routines passed via @code{-r|--routine}. Do not modify the supplied @code{%SYSINIT} routine to add site-specific startup items. Instead, create a @code{LCLINIT} routine in the @code{USER} namespace of one or more environments. @code{%SYSINIT} will automatically run @code{LCLINIT} each time it starts. @@ -522,6 +566,43 @@ DEFAULT.USER> Such expressions will be immediately evaluated, and the result printed on @code{@ref{$IO}}. +@node Debugging +@chapter Debugging +@cindex debugging + +@section Debugging Synopsis +FreeM includes an interactive debugger, entered using the @code{BREAK "DEBUG"} command. The debugger is also entered if @code{Ctrl-C} is pressed, @code{Ctrl-C} handling is enabled, and you are in direct mode. + +If you would like to enter the debugger automatically each time an error is encountered, add the following to your @code{LCLINIT} routine: + +@example +S $ETR="B ""DEBUG""" +@end example + +@section Debugging Commands +The debugger uses its own unique command language, where M commands are unavailable. Commands are as follows: + +@table @asis +@item @code{exit}, @code{quit} +Exits the debugger and returns to direct mode or normal program execution. +@item @code{e} @emph{glvn}, @code{examine} @emph{glvn} +Prints the value of @emph{glvn} to the terminal. +@item @code{t}, @code{trace} +Toggles @emph{trace mode} on and off. When trace mode is on, FreeM will display information about each @code{DO} or @code{GOTO} command encountered, including the routine which invoked the branch, which type of branch was invoked, and the target of the branch. +@item @code{s}, @code{step} +Single-steps through FreeM code command-by-command. +@item @code{n}, @code{next} +Single-steps through FreeM code line-by-line. +@item @code{c}, @code{cont}, @code{continue} +Resumes normal program execution, disabling single-step mode. +@item @code{bt}, @code{backtrace} +Produces a stack trace. +@item @code{h}, @code{halt} +Halts the process being debugged and returns control to the operating system. +@item @code{w [[+|-|?]@emph{}]}, @code{watch [[+|-|?]@emph{}]} +With no arguments, toggles watchpoints on and off. With @code{+}, adds @emph{} to the watchlist. With @code{-}, removes @emph{} from the watchlist. With @code{?}, queries the watch status of @emph{}. +@end table + @node Directives @chapter Directives @cindex directives @@ -4430,7 +4511,30 @@ A @code{REAL} is a numeric interpretatio @cindex data types, STRING @cindex types, STRING -A @code{STRING} is any data in FreeM. +The @code{STRING} is the fundamental FreeM data type. Other types are inferred from the context of their usage. + +@subsection String Rules + +The following rules apply to all FreeM strings: + +@itemize +@item Must not exceed 255 characters +@item Must not contain @code{$C(0)}, @code{$C(201)}, or @code{$C(202)} +@end itemize + +@subsection String Quoting Rules +Strings in FreeM must be surrounded in double quotes: + +@example +SET MYSTRING="This is a string literal" +@end example + +If you want to include double quotes inside of a string, simply double them: + +@example +SET MYSTRING="This is a ""string literal"" with embedded double quotes" +@end example + @node Custom Types (Classes) @section Custom Types (Classes) @@ -4469,7 +4573,7 @@ Optionally, one or more comma-delimited A value of up to 255 characters in length @end itemize -The percent sign will force the named global into the @code{SYSTEM} namespace of the current FreeM environment. +A leading percent sign in the global name will force the named global into the @code{SYSTEM} namespace of the current FreeM environment. @node Creating Globals @section Creating Globals @@ -5621,34 +5725,6 @@ Raised when an attempt is made to use a @end table -@node Debugging -@chapter Debugging -@cindex debugging - -FreeM includes an interactive debugger, entered using the @code{BREAK "DEBUG"} command. The debugger is also entered if @code{Ctrl-C} is pressed, @code{Ctrl-C} handling is enabled, and you are in direct mode. - -The debugger uses its own unique command language, where M commands are unavailable. Commands are as follows: - -@table @asis -@item @code{exit}, @code{quit} -Exits the debugger and returns to direct mode or normal program execution. -@item @code{e} @emph{glvn}, @code{examine} @emph{glvn} -Prints the value of @emph{glvn} to the terminal. -@item @code{t}, @code{trace} -Toggles @emph{trace mode} on and off. When trace mode is on, FreeM will display information about each @code{DO} or @code{GOTO} command encountered, including the routine which invoked the branch, which type of branch was invoked, and the target of the branch. -@item @code{s}, @code{step} -Single-steps through FreeM code command-by-command. -@item @code{n}, @code{next} -Single-steps through FreeM code line-by-line. -@item @code{c}, @code{cont}, @code{continue} -Resumes normal program execution, disabling single-step mode. -@item @code{bt}, @code{backtrace} -Produces a stack trace. -@item @code{h}, @code{halt} -Halts the process being debugged and returns control to the operating system. -@item @code{w [[+|-|?]@emph{}]}, @code{watch [[+|-|?]@emph{}]} -With no arguments, toggles watchpoints on and off. With @code{+}, adds @emph{} to the watchlist. With @code{-}, removes @emph{} from the watchlist. With @code{?}, queries the watch status of @emph{}. -@end table @node System Configuration @chapter System Configuration