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ALIAS

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E0300 Edition 3
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Defines an alias (alternative) name for a command or macro.

Syntax



   ALIAS name command

Aliases are useful for defining a new (shorter or longer) name for a command name or macro name. Aliases have higher precedence than command or macro names, and they can therefore be used to redefine (or conceal) commands or macros. When a new alias redefines a command, a warning is generated, indicating that a command has been hidden.

User defined aliases, created with the ALIAS command, are classified as user aliases. Several predefined aliases (command abbreviations) are automatically generated, and are classified as predefined aliases. Refer to the ALIASLIST and ALIASINIT commands.

Parameters


name

The name of the alias (the new name to be used in place of another). Alias names are restricted to 16 characters.

command

The command name to be used when the alias name is encountered. This can be any command or macro name. The command name is restricted to 32 characters.

Examples



   $nmdebug > printtableentrylength 6
   $200
   $nmdebug > alias tbl printtableentrylength
   $nmdebug > tbl 6
   $200

The above example assumes that a macro called printtableentrylength has been defined, and a typical macro invocation is displayed. Since the macro name is long, and difficult to enter, an alias named TBL is defined. The shorter alias name can now be used in place of the longer macro name.

   $nmdebug > alias loop foreach
   $nmdebug > loop j '1 2 3' {wl j}
   $1
   $2
   $3

Create an alias named LOOP that is the same as the FOREACH command.

   $nmdat > macro concealexit { wl "type EXIT to exit."}
   $nmdat > alias e concealexit
   A command is hidden by this new alias.  (warning #71)
   $nmdat > e
   type EXIT to exit.

In this example, the single character command e (for EXIT) is protected by an alias, that conceals (hides) the original command. Note that a warning message is generated whenever a command name is concealed by an alias definition.

   $nmdat > alias one two
   $nmdat > alias two three
   $nmdat > alias three one
   $nmdat > one
   Circular ALIAS error. Recursive ALIAS definition(s). (error #2445)

It is legal for an alias (for example, one in the example above) to refer to another alias (two in the example above), so long as the chain of aliases does not wrap back onto itself. Recursive aliases are detected, and an error is generated.

   $nmdat > alias showtime "wl time"
   $nmdat > aliasl showtime
   alias showtime wl time   /* user
   $nmdat > showtime
   Unknown command.  (error #6105)
      Command "showtime" was aliased to "wl time".

Note that alias command names are restricted to simple command or macro names. In the above example, the command wl time was assumed to be the name of a command or macro. Since no match was found in the command or macro table, an error is generated. Macros should be used when more complex command lists or commands with parameters are desired.

Related commands: ALIASINIT, ALIASL, ALIASD.

Limitations, Restrictions


A maximum of 60 alias definitions are currently supported.

The alias command (the replacement name) is limited to command and macro names; no parameters or complex command lists are allowed. Refer to the showtime example above.

The ALIASD command cannot be aliased.

No testing is performed for invalid characters within the name or command parameters.


CAUTION: The output format of all System Debug commands is subject to change without notice. Programs that are developed to postprocess System Debug output should not depend on the exact format (spacing, alignment, number of lines, uppercase or lowercase, or spelling) of any System Debug command output.




ABORT


ALIASD[EL]