view docs/manual/x237.html @ 460:3d53f2e8d0e0

Allow macros to shadow instructions that are not supported by current CPU. When assembling in 6809 mode, 6309 instructions should be usable as macros. When assembling in 6309 mode, instructions not valid on the 6309 should be usable as macros.
author William Astle <lost@l-w.ca>
date Wed, 28 Feb 2018 20:43:14 -0700
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>3.4. Symbols</A
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>Symbols have no length restriction. They may contain letters, numbers, dots,
dollar signs, and underscores. They must start with a letter, dot, or
underscore.</P
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>LWASM also supports the concept of a local symbol. A local symbol is one
which contains either a "?" or a "@", which can appear anywhere in the symbol.
The scope of a local symbol is determined by a number of factors. First,
each included file gets its own local symbol scope. A blank line will also
be considered a local scope barrier. Macros each have their own local symbol
scope as well (which has a side effect that you cannot use a local symbol
as an argument to a macro). There are other factors as well. In general,
a local symbol is restricted to the block of code it is defined within.</P
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>By default, unless assembling to the os9 target, a "$" in the symbol will
also make it local.  This can be controlled by the "dollarlocal" and
"nodollarlocal" pragmas.  In the absence of a pragma to the contrary, for
the os9 target, a "$" in the symbol will not make it considered local while
for all other targets it will.</P
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