how do I check to see if a variable already exists?

Testing if a Variable Is Defined - Python Cookbook [Book] - O'Reilly

If you know for sure which namespace the variable is in (i.e., specifically locals or specifically globals ), you can also use methods such as has_key or get on ...

Is there another way to check if a variable exists? - Scripting Support

But the problem is that my variable is variable = false so it won't get past the ifs. Is there any other way to check if a variable exists? 4 ...

Check if a variable which only exists at runtime but only in certain ...

I'm trying to do is find out where an expression rule is being used at runtime and logging that information for us to help diagnose a performance issue.

st: to check if a variable already exists - Stata

In MATLAB, how can you check if a variable is not defined? - Quora

In MATLAB, you can check if a variable is not defined by using the exist() function. The exist() function takes a string input that specifies the name of the ...

Ensuring variable existence - Adobe Support

Before relying on a variable's existence in an application page, you can test to see if it exists by using the IsDefined function. To check ...

How to find out if a variable has been defined - The Universe Divided

As an example: “window.doesnotexist==null” results in true. Be careful not to overwrite stuff that already does exist in the window. 1.

Microflow for checking if something already exists | Mendix Forum

When you click on the save button, run it through a validation microflow to check if the category already exists in db.

"Global Variable ..... Already Exists" Error - SOLIDWORKS Forums

Anyone know what I can do to try and be able to edit a global variable value in a multi-configuration part using either: equations dialog, ...

Checking if a variable exists with strict_variables set - Jekyll Talk

Now, checking for existence of a variable not failing with strict_variables = true , one suggestion I found is this {% if page contains language ...

Test if variable exists? - Getting Started - Xojo Programming Forum

Use a Variant or Auto. You still have to know the variable name but you can test to see if it is null (not initialized). Use If MyVariant. · Use ...

checking if variable exists code | Javascript - Coding Forums

Hey, Can someone show my how to change the code below to check to see if a variable exists rather than if the variable contains an empty ...

How to check variable if present or not ? - Oracle Forums

date from sysdate, but if it is already define then do not get from sysdate. so : IF :global.gdate is define (or null or declare maybe) then null --(do nothing ...

How to check if a variable is defined in JavaScript - DEV Community

Are you annoyed by the following error and want to put check to see if a variable exists before accessing them?

Check if a variable exists - GoAnywhere Forum

emptyString} or just '' (quote/quote). Then, inside your Project, test to see if the variable is empty ... If ${ IsEmpty( VarName ) }...

Check if variable exists - Developer - Tryton Discussion

Is there a way to check from within a relatorio template (odt in my case), if a variable that I want to access actually exists in my data?

How to determine if a bash variable is empty? - Server Fault

Testing for a variable set to the empty string can also be done using [ -z "${VAR-set}" ] . – nwellnhof. Commented May ...

info exists - the Tcler's Wiki!

info exists returns 0 for variables that exist but are undefined. This can happen, for example, with trace, because if a trace is set on a nonexisting variable, ...

"Table variable already exists" during install | Drupal.org

Don't want to delete everything and reload (done this twice), does anyone know what file the table var is in so I can delete it and reinstall?

Need to check if a variable already exists as a worksheet name

If there isn't a worksheet with that name, it names the current sheet "AccountCode", but if it finds a duplicate then it changes the "001" to " ...