* mu-guile.texi: start of mu-guile documentation (WIP)

guile/mu-guile.texi

@@ -33,8 +33,10 @@ programming language.
 
 @menu
 * Introduction::
-* Installation::
-* First steps::
+* Getting started::
+* Initialization::
+* Messages::
+* Contacts::
 
 Appendices
 
@@ -56,19 +58,19 @@ extension language.
 @t{mu-guile} connects @t{mu} and @t{guile}, and allows you to easily write
 programs to do things with your e-mails.
 
-@c @menu
-@c * Why another e-mail client?::
-@c * What mu4e does and doesn't do::
-@c @end menu
+@node Getting started
+@chapter Getting started
 
-@c @node Why another e-mail client?
-@c @section Why another e-mail client?
+@menu
+* Installation::
+* First steps::
+@end menu
 
-@c @node What mu4e does and doesn't do
-@c @section What mu4e does and doesn't do
+This chapter walks you through the installation and some basic steps to ensure
+things work correctly.
 
 @node Installation
-@chapter Installation
+@section Installation
 
 @t{mu-guile} is part of @t{mu} - by installing the latter, the former will be
 installed as well. Note, however, that @t{mu-guile} requires you to have
@@ -123,7 +125,7 @@ following to your @file{~/.guile}:
 After this, you should be ready to go.
 
 @node First steps
-@chapter First steps
+@section First steps
 
 Assuming @t{mu-guile} has been installed correctly (@ref{Installation}), and
 also assuming that you have already indexed your e-mail messages (if
@@ -167,6 +169,205 @@ scheme@(guile-user)> (for-each
                         (mu:message-list "hello"))
 @end verbatim
 
+@node Initialization
+@chapter Initialization
+
+It is of course possible to write separate programs with @t{mu-guile}, but for
+now we'll do things @emph{interactively}, i.e., from the Guile-prompt
+(``@abbr{REPL}'').
+
+We start our @t{mu-guile} session by starting @t{guile}:
+
+@verbatim
+$ guile
+GNU Guile 2.0.3.82-a2c66
+Copyright (C) 1995-2011 Free Software Foundation, Inc.
+
+Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
+This program is free software, and you are welcome to redistribute it
+under certain conditions; type `,show c' for details.
+
+Enter `,help' for help.
+scheme@(guile-user)>
+@end verbatim
+
+Now, the first thing we need to do is load the @t{mu-guile} modules;
+currently, there are three available:
+
+@itemize
+@item @code{mu} - initialization, functions to get messages, contacts
+@item @code{mu message} - functions to deal with a single message
+@item @code{mu contact} - functions to deal with a single contact
+@end itemize
+
+Let's simply load all of them:
+
+@verbatim
+scheme@(guile-user)> (use-modules (mu) (mu message) (mu contact)) 
+@end verbatim
+
+Assuming you have installed everything correctly, the first time you do this,
+@t{guile} will probably respond by showing some message about compiling the
+modules, and then end with another prompt.
+
+Before we can do anything with @t{mu guile}, we need to initialize the
+system. The reason as to not do this automatically is to enable people to use
+non-default places to keep there @t{mu} data files.
+
+We can initialize the system with:
+
+@verbatim
+scheme@(guile-user)> (mu:initialize)    
+@end verbatim
+
+Which will use the default location of @file{~/.mu}. Or, instead, if you keep
+your @t{mu} data in a non-standard place:
+
+@verbatim
+scheme@(guile-user)> (mu:initialize "/path/to/my/mu/") 
+@end verbatim
+
+If all worked up until here, we're ready to go with @t{mu-guile}.
+
+@node Messages
+@chapter Messages
+
+In this chapter, we discuss how to find messages, and then how to do various
+things with them.
+
+@menu
+* Finding messages::
+* Message functions::
+@end menu
+
+@node Finding messages
+@section Finding messages
+Now we are ready to retrieve some messages from the system. There are two
+principle functions to do this:
+
+@itemize
+@item @code{(mu:message-list [<search-expression>])}  
+@item @code{(mu:for-each-message <function> [<search-expression>])}  
+@end itemize
+
+The first function, @code{mu:message-list} returns a list of all messages
+matching @t{<search-expression>}; if you leave @t{<search-expression>} out, it
+returns @emph{all} messages.
+
+For example, to get all messages with @emph{coffee} in the subject line, you
+could do:
+
+@verbatim
+scheme@(guile-user)> (mu:message-list "subject:coffee")
+$1 = (#<<mu-message> 9040640> #<<mu-message> 9040630>
+      #<<mu-message> 9040570>)
+@end verbatim
+
+So, we get a list with three @t{<mu-message>} objects. We'll discuss them in a
+bit more detail in the next section, but let's just use the @code{subject}
+function ('method') provided by @t{<mu-message>} objects to retrieve the
+subject-field.
+
+For your convenience, @t{guile} has saved the result in @t{$1}, so to get the
+subject of the first message in the list, we can do:
+
+@verbatim
+scheme@(guile-user)> (subject (car $1))
+$2 = "Re: best coffee ever!"
+@end verbatim
+
+The second function we mentioned, @code{mu:for-each-message}, executes some
+function for each message matched by the search expression (or @emph{all}
+message if the search expression is omitted).
+
+@verbatim
+scheme@(guile-user)> (mu:for-each-message
+                       (lambda(msg)
+                         (display (subject msg))
+                         (newline))
+                      "subject:coffee")
+Re: best coffee ever!
+best coffee ever!
+scheme@(guile-user)>
+@end verbatim
+
+Using @code{mu:message-list} and/or
+@code{mu:for-each-message}@footnote{Implementation node:
+@code{mu:message-list} is implemented in terms of @code{mu:for-each-message},
+not the other way around. Due to the way @t{mu} works,
+@code{mu:for-each-message} is rather more efficient than a combination for
+@code{for-each} and @code{mu:message-list}} and a couple of @t{<mu-message>}
+methods, together with that Guile/Scheme provides should allow for many
+interesting programs.
+
+@node Message functions
+@section Message functions
+
+Now that we've seen how to retrieve lists of message objects
+(@code{<mu-message>}), let's see what we can do with such an object.
+
+@code{<mu-message>} defines the following methods
+@footnote{A note on naming: functions we have seen before --
+@code{mu:initialize}, @code{mu:message-list} and @code{mu:for-each-message}
+are prefixed with @t{mu:}. This is not the case for the @code{<mu-message>}
+methods to be discussed next, such as the methods @code{subject} and
+@code{from}. Reason for this is that it is not @emph{needed}, since these
+methods only recognized for @code{<mu-message>} objects, and do not affect
+anything else, while the @code{mu:}-prefixed are 'globally visible' and thus
+we need to be careful about naming conflicts}
+ that all only take a single
+@code{<mu-message>} object as a parameter. We won't go into the exact meanings
+for all of these functions here - for the details about various flags /
+properties, please refer to the @t{mu-find} man-page.
+
+@itemize
+@item @code{bcc}: the @t{Bcc} field of the message, or @t{#f} if there is none      
+@item @code{body-html}: : the html body of the message, or @t{#f} if there is none
+@item @code{body-txt}: the plain-text body of the message, or @t{#f} if there is none 
+@item @code{cc}: the @t{Bcc} field of the message, or @t{#f} if there is none         
+@item @code{date}: the @t{Date} field of the message, or 0 if there is none       
+@item @code{flags}: list of message-flags for this message      
+@item @code{from}: the @t{From} field of the message, or @t{#f} if there is none
+@item @code{maildir}: the maildir this message lives in, or @t{#f} if there is none    
+@item @code{message-id}: the @t{Message-Id} field of the message, or @t{#f} if there is none
+@item @code{path}: the file system path for this message      
+@item @code{priority}: the priority of this message (either @t{mu:low}, @t{mu:normal}
+or @t{mu:high}
+@item @code{references}: the list of messages (message-ids) this message
+refers to in the @t{References:} header
+@item @code{size}: size of the message in bytes        
+@item @code{subject}: the @t{Subject} field of the message, or @t{#f} if there is none.   
+@item @code{tags}: list of tags for this message          
+@item @code{to}: the sender of the message, or @t{#f} if there is none.         
+@end itemize
+
+With these functions, we can query messages for their properties; for example:
+
+@verbatim
+scheme@(guile-user)> (define msg (car (mu:message-list "snow")))
+scheme@(guile-user)> (subject msg)
+$1 = "Re: Running in the snow is beautiful"
+scheme@(guile-user)> (flags msg)
+$2 = (mu:replied mu:seen)
+scheme@(guile-user)> (strftime "%F" (localtime (date msg)))
+$3 = "2011-01-15"
+@end verbatim
+
+There are a couple more functions:
+@itemize
+@item @code{(header <mu-message> "<header-name>")} returns an arbitrary message
+header (or @t{#f} if not found) -- e.g. @code{(header msg "User-Agent")}
+@item @code{(contacts <mu-message> contact-type)} which returns a list  
+of contacts (names/e-mail addresses in the To/From/Cc/Bcc-fields).
+@xref{Contacts}.
+
+@end itemize
+
+
+@node Contacts
+@chapter Contacts
+
+
 @node GNU Free Documentation License
 @appendix GNU Free Documentation License