HP 3000 Manuals HP 3000 Manuals
Use X Register
Purpose
Sets or retrieves the X register.
Default Syntax
[n] $x
where n represents a count that, if specified, moves to the X register.
Description
This command enables you to pass integers to and from macros and the HP
EDIT calculator X register. The X register resides at the top of a
four-register computational stack accessible through the Calculate
command.
Specifying A Count
If you specify a count before executing this command, the value is saved
in the X register, replacing the previous value. If you do not specify a
count, HP EDIT places the current value of the X register into the count
for use by the next command.
Ordinarily, if you specify a count before executing a macro, the macro
repeats the number of times specified. However, if the Use X Register
command is the first command executed within the macro, the specified
count is loaded into the X register and the macro executes only once.
This process enables you to use the X register to pass a parameter (the
count) to a macro.
[REV DEL]
Syntax Considerations
In order to use this command within a macro, you must properly construct
the macro using correct syntax. Refer to the Define Macro command for
information about required syntax.
Since the standard Meta key (ESC) is displayed as ^[ when inserted in a
macro, HP EDIT provides the dollar sign ($) as an alternate Meta key.
Consequently, you should use the recommended syntax of $x within a macro.
Procedure
To place a value in the X register:
1. Type a count representing the value desired.
2. Press ESC and the x key. HP EDIT stores the value in the X
register.
To retrieve the X register value:
1. Press ESC and the x key. HP EDIT displays the value of the X
register as a count on the message line.
Examples
To interactively delete the next n lines, where n represents the current
X register value:
1. Press ESC and the x key. HP EDIT displays the value of the X
register as the count on the message line.
2. Execute the Delete Line (D) command. HP EDIT deletes the number
of lines displayed as the count.
To define and execute a macro that shifts the current line the number of
spaces specified in the count:
1. Execute the Insert Line (L) command to insert a new line and enter
Text Entry mode.
2. Type the following macro, which saves the macro count in the X
register, invokes the calculator, stores the count into the shift
count, exits the calculator, and finally executes a shift to the
right:
m>=$x$+s>^m>
3. Exit Text Entry mode by pressing / and Return.
4. Define the macro using the Define Macro (z) command. HP EDIT
deletes the macro from the screen and displaying the following
message:
1 macro defined
5. Type the number 5 as the count.
6. Execute the macro using the Execute Macro (m) command. When
prompted for the command name, type >. HP EDIT shifts the current
line 5 spaces to the right. Note that this shift count remains
for subsequent shift commands until you change it or leave the
session.
Related Commands
Calculate
Use Y Register