Basic Examples (2) 

Check if a given file exists:

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Verify a file exists:

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When a file does not exist, create one:

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Scope (1) 

Add to a databin if it exists, otherwise create a new one:

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Applications (2) 

Deploy an API with a permissions group if one already exists:

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Create a list of object references for objects that do not exist:

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Create only one of the object references:

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Create a tool that finds the first existent object on the list:

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Properties and Relations (2) 

When an object does not exist and no default is given, Missing is used.:

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The default does not evaluate until it is needed:

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In this case it evaluates:

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