mirror of
https://github.com/michaelcmartin/Ophis.git
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203 lines
2.9 KiB
HTML
203 lines
2.9 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<HTML
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><HEAD
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><TITLE
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>Aliasing</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
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REL="HOME"
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TITLE="Programming with Ophis"
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HREF="book1.html"><LINK
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REL="UP"
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TITLE="Labels and aliases"
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HREF="c200.html"><LINK
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REL="PREVIOUS"
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TITLE="Anonymous labels"
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HREF="x214.html"><LINK
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REL="NEXT"
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TITLE="Headers, Libraries, and Macros"
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HREF="c236.html"></HEAD
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><BODY
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CLASS="SECTION"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Programming with Ophis</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="x214.html"
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ACCESSKEY="P"
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><<< Previous</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Labels and aliases</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="c236.html"
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ACCESSKEY="N"
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>Next >>></A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="SECTION"
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><H1
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CLASS="SECTION"
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><A
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NAME="AEN225"
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>Aliasing</A
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></H1
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><P
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> Rather the reverse of anonymous labels, aliases are names
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given to specific memory locations. These make it easier to
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keep track of important constants or locations. The KERNAL
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routines are a good example of constants that deserve names.
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To assign the traditional name <TT
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CLASS="LITERAL"
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>chrout</TT
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> to
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the routine at $FFD2, simply give the directive:
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</P
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><TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
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>.alias chrout $ffd2</PRE
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></TD
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></TR
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></TABLE
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><P
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>And change the <KBD
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CLASS="USERINPUT"
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>jsr</KBD
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> command
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to:</P
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><TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><PRE
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CLASS="PROGRAMLISTING"
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> jsr chrout</PRE
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></TD
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></TR
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></TABLE
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><P
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> The final version of the code is in <A
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HREF="x461.html"
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><I
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><I
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>tutor2.oph</I
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></I
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></A
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>. It should
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assemble to exactly the same program as <A
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HREF="a454.html#TUTOR1-SRC"
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><I
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><I
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>tutor1.oph</I
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></I
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></A
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>.
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</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="x214.html"
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ACCESSKEY="P"
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><<< Previous</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="book1.html"
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ACCESSKEY="H"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="c236.html"
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ACCESSKEY="N"
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>Next >>></A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>Anonymous labels</TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="c200.html"
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ACCESSKEY="U"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>Headers, Libraries, and Macros</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |