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The command must be followed by a '+' or '-' character to switch the
option on or off respectively.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .debuginfo      +       ; Generate debug info
  
</PRE>
</CODE></BLOCKQUOTE>
</P>


<H2><A NAME=".DEFINE"></A> <A NAME="ss10.18">10.18</A> <A HREF="ca65.html#toc10.18"><CODE>.DEFINE</CODE></A>
</H2>


<P>Start a define style macro definition. The command is followed by an
identifier (the macro name) and optionally by a list of formal arguments
in braces.
See section 
<A HREF="ca65-11.html#macros">Macros</A>.</P>


<H2><A NAME=".DEFINED"></A> <A NAME="ss10.19">10.19</A> <A HREF="ca65.html#toc10.19"><CODE>.DEF, .DEFINED</CODE></A>
</H2>


<P>Builtin function. The function expects an identifier as argument in braces.
The argument is evaluated, and the function yields "true" if the identifier
is a symbol that is already defined somewhere in the source file up to the
current position. Otherwise the function yields false. As an example, the
<CODE>
<A HREF="#.IFDEF">.IFDEF</A></CODE> statement may be replaced by</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .if     .defined(a)
  
</PRE>
</CODE></BLOCKQUOTE>
</P>


<H2><A NAME=".DESTRUCTOR"></A> <A NAME="ss10.20">10.20</A> <A HREF="ca65.html#toc10.20"><CODE>.DESTRUCTOR</CODE></A>
</H2>


<P>Export a symbol and mark it as a module destructor. This may be used
together with the linker to build a table of destructor subroutines that
are called by the startup code.</P>
<P>Note: The linker has a feature to build a table of marked routines, but it
is your code that must call these routines, so just declaring a symbol as
constructor does nothing by itself.</P>
<P>A destructor is always exported as an absolute (16 bit) symbol. You don't
need to use an additional <CODE>.export</CODE> statement, this is implied by
<CODE>.destructor</CODE>. It may have an optional priority that is separated by a
comma. Higher numerical values mean a higher priority. If no priority is
given, the default priority of 7 is used. Be careful when assigning
priorities to your own module destructors so they won't interfere with the
ones in the cc65 library.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .destructor     ModuleDone
        .destructor     ModDone, 16
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>See the <CODE>
<A HREF="#.CONDES">.CONDES</A></CODE> and <CODE>
<A HREF="#.CONSTRUCTOR">.CONSTRUCTOR</A></CODE> commands and the separate
section 
<A HREF="ca65-14.html#condes">Module constructors/destructors</A> explaining
the feature in more detail.</P>


<H2><A NAME=".DWORD"></A> <A NAME="ss10.21">10.21</A> <A HREF="ca65.html#toc10.21"><CODE>.DWORD</CODE></A>
</H2>


<P>Define dword sized data (4 bytes) Must be followed by a sequence of
expressions.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .dword  $12344512, $12FA489
  
</PRE>
</CODE></BLOCKQUOTE>
</P>


<H2><A NAME=".ELSE"></A> <A NAME="ss10.22">10.22</A> <A HREF="ca65.html#toc10.22"><CODE>.ELSE</CODE></A>
</H2>


<P>Conditional assembly: Reverse the current condition.</P>


<H2><A NAME=".ELSEIF"></A> <A NAME="ss10.23">10.23</A> <A HREF="ca65.html#toc10.23"><CODE>.ELSEIF</CODE></A>
</H2>


<P>Conditional assembly: Reverse current condition and test a new one.</P>


<H2><A NAME=".END"></A> <A NAME="ss10.24">10.24</A> <A HREF="ca65.html#toc10.24"><CODE>.END</CODE></A>
</H2>


<P>Forced end of assembly. Assembly stops at this point, even if the command
is read from an include file.</P>


<H2><A NAME=".ENDENUM"></A> <A NAME="ss10.25">10.25</A> <A HREF="ca65.html#toc10.25"><CODE>.ENDENUM</CODE></A>
</H2>


<P>End a <CODE>
<A HREF="#.ENUM">.ENUM</A></CODE> declaration.</P>


<H2><A NAME=".ENDIF"></A> <A NAME="ss10.26">10.26</A> <A HREF="ca65.html#toc10.26"><CODE>.ENDIF</CODE></A>
</H2>


<P>Conditional assembly: Close a <CODE>
<A HREF="#.IF">.IF...</A></CODE> or
<CODE>
<A HREF="#.ELSE">.ELSE</A></CODE> branch.</P>


<H2><A NAME=".ENDMACRO"></A> <A NAME="ss10.27">10.27</A> <A HREF="ca65.html#toc10.27"><CODE>.ENDMAC, .ENDMACRO</CODE></A>
</H2>


<P>End of macro definition (see section 
<A HREF="ca65-11.html#macros">Macros</A>).</P>


<H2><A NAME=".ENDPROC"></A> <A NAME="ss10.28">10.28</A> <A HREF="ca65.html#toc10.28"><CODE>.ENDPROC</CODE></A>
</H2>


<P>End of local lexical level (see <CODE>
<A HREF="#.PROC">.PROC</A></CODE>).</P>


<H2><A NAME=".ENDREPEAT"></A> <A NAME="ss10.29">10.29</A> <A HREF="ca65.html#toc10.29"><CODE>.ENDREP, .ENDREPEAT</CODE></A>
</H2>


<P>End a <CODE>
<A HREF="#.REPEAT">.REPEAT</A></CODE> block.</P>


<H2><A NAME=".ENDSCOPE"></A> <A NAME="ss10.30">10.30</A> <A HREF="ca65.html#toc10.30"><CODE>.ENDSCOPE</CODE></A>
</H2>


<P>End of local lexical level (see <CODE>
<A HREF="#.SCOPE">.SCOPE</A></CODE>).</P>


<H2><A NAME=".ENDSTRUCT"></A> <A NAME="ss10.31">10.31</A> <A HREF="ca65.html#toc10.31"><CODE>.ENDSTRUCT</CODE></A>
</H2>


<P>Ends a struct definition. See the <CODE>
<A HREF="#.STRUCT">.STRUCT</A></CODE>
command and the separate section named 
<A HREF="ca65-13.html#structs">&quot;Structs   and unions&quot;</A>.</P>


<H2><A NAME=".ENUM"></A> <A NAME="ss10.32">10.32</A> <A HREF="ca65.html#toc10.32"><CODE>.ENUM</CODE></A>
</H2>


<P>Start an enumeration. This directive is very similar to the C <CODE>enum</CODE>
keyword. If a name is given, a new scope is created for the enumeration,
otherwise the enumeration members are placed in the enclosing scope.</P>
<P>In the enumeration body, symbols are declared. The first symbol has a value
of zero, and each following symbol will get the value of the preceeding plus
one. This behaviour may be overriden by an explicit assignment. Two symbols
may have the same value.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .enum   errorcodes
                no_error
                file_error
                parse_error
        .endenum
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>Above example will create a new scope named <CODE>errorcodes</CODE> with three
symbols in it that get the values 0, 1 and 2 respectively. Another way
to write this would have been:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .scope  errorcodes
                no_error        = 0
                file_error      = 1
                parse_error     = 2
        .endscope
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>Please note that explicit scoping must be used to access the identifiers:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .word   errorcodes::no_error
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>A more complex example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .enum
                EUNKNOWN        = -1
                EOK
                EFILE
                EBUSY
                EAGAIN
                EWOULDBLOCK     = EAGAIN
        .endenum
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>In this example, the enumeration does not have a name, which means that the
members will be visible in the enclosing scope and can be used in this scope
without explicit scoping. The first member (<CODE>EUNKNOWN</CODE>) has the value -1.
The value for the following members is incremented by one, so <CODE>EOK</CODE> would
be zero and so on. <CODE>EWOULDBLOCK</CODE> is an alias for <CODE>EGAIN</CODE>, so it has an
override for the value using an already defined symbol.</P>


<H2><A NAME=".ERROR"></A> <A NAME="ss10.33">10.33</A> <A HREF="ca65.html#toc10.33"><CODE>.ERROR</CODE></A>
</H2>


<P>Force an assembly error. The assembler will output an error message
preceeded by "User error" and will <EM>not</EM> produce an object file.</P>
<P>This command may be used to check for initial conditions that must be
set before assembling a source file.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .if     foo = 1
        ...
        .elseif bar = 1
        ...
        .else
        .error  "Must define foo or bar!"
        .endif
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>See also the <CODE>
<A HREF="#.WARNING">.WARNING</A></CODE> and <CODE>
<A HREF="#.OUT">.OUT</A></CODE> directives.</P>


<H2><A NAME=".EXITMACRO"></A> <A NAME="ss10.34">10.34</A> <A HREF="ca65.html#toc10.34"><CODE>.EXITMAC, .EXITMACRO</CODE></A>
</H2>


<P>Abort a macro expansion immidiately. This command is often useful in
recursive macros. See separate section 
<A HREF="ca65-11.html#macros">Macros</A>.</P>


<H2><A NAME=".EXPORT"></A> <A NAME="ss10.35">10.35</A> <A HREF="ca65.html#toc10.35"><CODE>.EXPORT</CODE></A>
</H2>


<P>Make symbols accessible from other modules. Must be followed by a comma
separated list of symbols to export, with each one optionally followed by
an address specification. The default is to export the symbol with the
address size it actually has. The assembler will issue a warning, if the
symbol is exported with an address size smaller than the actual address
size.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .export foo
        .export bar: far
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>See: <CODE>
<A HREF="#.EXPORTZP">.EXPORTZP</A></CODE></P>


<H2><A NAME=".EXPORTZP"></A> <A NAME="ss10.36">10.36</A> <A HREF="ca65.html#toc10.36"><CODE>.EXPORTZP</CODE></A>
</H2>


<P>Make symbols accessible from other modules. Must be followed by a comma
separated list of symbols to export. The exported symbols are explicitly
marked as zero page symols.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .exportzp  foo, bar
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>See: <CODE>
<A HREF="#.EXPORT">.EXPORT</A></CODE></P>


<H2><A NAME=".FARADDR"></A> <A NAME="ss10.37">10.37</A> <A HREF="ca65.html#toc10.37"><CODE>.FARADDR</CODE></A>
</H2>


<P>Define far (24 bit) address data. The command must be followed by a
sequence of (not necessarily constant) expressions.</P>
<P>Example:</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .faraddr        DrawCircle, DrawRectangle, DrawHexagon
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>See: <CODE>
<A HREF="#.ADDR">.ADDR</A></CODE></P>


<H2><A NAME=".FEATURE"></A> <A NAME="ss10.38">10.38</A> <A HREF="ca65.html#toc10.38"><CODE>.FEATURE</CODE></A>
</H2>


<P>This directive may be used to enable one or more compatibility features
of the assembler. While the use of <CODE>.FEATURE</CODE> should be avoided when
possible, it may be useful when porting sources written for other
assemblers. There is no way to switch a feature off, once you have
enabled it, so using</P>
<P>
<BLOCKQUOTE><CODE>
<PRE>
        .FEATURE        xxx
  
</PRE>
</CODE></BLOCKQUOTE>
</P>
<P>will enable the feature until end of assembly is reached.</P>
<P>The following features are available:</P>
<P>
<DL>

<DT><B><CODE>dollar_is_pc</CODE></B><DD><P>The dollar sign may be used as an alias for the star (`*'), which
gives the value of the current PC in expressions.
Note: Assignment to the pseudo variable is not allowed.</P>

<DT><B><CODE>labels_without_colons</CODE></B><DD><P>Allow labels without a trailing colon. These labels are only accepted,
if they start at the beginning of a line (no leading white space).</P>

<DT><B><CODE>loose_string_term</CODE></B><DD><P>Accept single quotes as well as double quotes as terminators for string
constants.</P>

<DT><B><CODE>loose_char_term</CODE></B><DD><P>Accept single quotes as well as double quotes as terminators for char
constants.</P>

<DT><B><CODE>at_in_identifiers</CODE></B><DD><P>Accept the at character (`@') as a valid character in identifiers. The
at character is not allowed to start an identifier, even with this
feature enabled.</P>