{{htmlmetatags>metatag-description:(ICL George 3 and George 4 GIN macro index)}}
====== GIN Macros ======

A macro definition consists of a series of source records enclosed between the directives #MACRO and #NORMAL. It may contain anything except the directives #GO, #MACRO, #USE and #READ. Each macro has a name, consisting of a letter followed by 0 to 7 alphanumeric characters. A macro name must be unique, and its first four characters must be different from the first four characters of any instruction mnemonic.

At any point in a macro definition a formal parameter may be included.  A formal parameter consists of the character % followed by a letter. (It is not possible to use % for any other purpose within a macro definition). When the macro is called, %A will be replaced by the first actual parameter in the call line, %B by the second, and so on.

The absence of restrictions on what may appear on a line allows directives, macro calls, labels, or even erroneous lines to be stored. Storing erroneous lines can be useful for parameter validation. Suppose for example that %B is expected to be an expression whose value does not exceed that of identifier **AMAX**: then the following coding would cause the parameter to be checked:
<code>#SKI %B>AMAX$AMAX
! PARAMETER OUT OF RANGE: %B
#SKI %B>AMAX$AMAX<1$1
(
body of macro
)</code>

[[george:table-macroA|A]]
[[george:table-macroB|B]]
[[george:table-macroC|C]]
[[george:table-macroD|D]]
[[george:table-macroE|E]]
[[george:table-macroF|F]]
[[george:table-macroG|G]]
[[george:table-macroH|H]]
[[george:table-macroI|I]]
[[george:table-macroJ|J]]
[[george:table-macroK|K]]
[[george:table-macroL|L]]
[[george:table-macroM|M]]
[[george:table-macroN|N]]
[[george:table-macroO|O]]
[[george:table-macroP|P]]
[[george:table-macroQ|Q]]
[[george:table-macroR|R]]
[[george:table-macroS|S]]
[[george:table-macroT|T]]
[[george:table-macroU|U]]
[[george:table-macroV|V]]
[[george:table-macroW|W]]
[[george:table-macroX|X]]
[[george:table-macroY|Y]]
[[george:table-macroZ|Z]]