HP 3000 Manuals HP 3000 Manuals
Setting User-Defined Variables
Variables are easily set using the SETVAR command. The command
parameters are the variable name and its value. The value can be
specified as a single numeric value, a character string, a boolean value,
an expression, or the value of another variable. The SHOWVAR command
displays the current value of a variable.
In the following example, several variables are set to numeric, string,
and boolean values. The SHOWVAR command is used to display the current
value of specified variables. Note that wildcard characters, such as the
at sign (@), question mark (?), and pound sign (#), can be used to
display multiple variables that have similar names.
:SETVAR CM_PAY_AMT 1000
:SETVAR CM_FIRST_NAME "CAROL"
:SETVAR CM_LAST_NAME "SMITH"
:SETVAR CM_DONE FALSE
:SHOWVAR CM_PAY_AMT,@NAME
CM_PAY_AMT = 1000
CM_FIRST_NAME = CAROL
CM_LAST_NAME = SMITH
Defining Variable Type
The variable type is defined by your input. Quotation marks specify that
the enclosed phrase is a character string. In the previous example, the
first and last names are interpreted as string variables. The value
1000, an unquoted numeric string, is interpreted as an integer value.
The unquoted word, FALSE, sets the variable to a boolean value.
Expressions can also be used to set variable values.
An unquoted string is interpreted as a variable name, not a character
string. In such cases, the first variable is loaded with the value of
the second variable. The content of the second variable determines the
variable type of the new one. In the following example, one new variable
CM_NAME is set to the current value of CM_FIRST_NAME, which was set in a
previous example.
:SETVAR CM_NAME CM_FIRST_NAME
:SHOWVAR CM_NAME
CM_NAME = CAROL
Displaying User-Defined Variables
As shown in the previous examples, the SHOWVAR command displays the
current value of specified user-defined variables. If no parameter
information is provided, all user-defined variables for the session are
displayed in the order they were created.
:SHOWVAR
CM_DONE = FALSE
CM_FIRST_NAME = CAROL
CM_LAST_NAME = SMITH
CM_PAY_AMT = 1000
CM_NAME = CAROL
Naming Variables
Variables remain set for the duration of the session unless they are
deleted or reset to a new value. To avoid collisions with variable names
used in command files and UDCs, develop a naming convention that creates
unique variable names.
The naming convention used in the preceding examples adds a common prefix
to all variables in the command file. In this case, all variables are
preceded by CM_. Such a prefix could be the name or abbreviated name of
the command file itself. This would provide immediate recognition of the
command file that set the variable.
Deleting User-Defined Variables
The DELETEVAR command deletes user-defined variables. It is easier to
delete variables in a single maintenance step if each variable name is
preceded by a command file identifier. The following example shows how
all user-defined variables in the CM command file are deleted by
specifying the command file identifier and a wildcard character.
:DELETEVAR CM_@