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This is a tracking category for CS1 citations that have empty parameter whose names are not known.

Help desk

This error message highlights CS1|2 templates that hold empty parameters with names that are not known to a given CS1|2 template. This error message is a companion to Unknown parameter |xxxx= ignored.

Empty positional parameters, which typically look like two adjacent pipes in a template, | |, or a pipe and then the end of the template, |}}, are identified as numbered parameters: |1=. Similarly, a pipe followed by an HTML comment that encloses everything before the next pipe or closing brace, | <!--<param name/value pair>--> | will be identified as an empty numbered parameter. Parameters that have both a pipe and an equal sign but do not have a name are identified as empty-string parameters: |= or | = → |(empty string)=. Various templates that wrap CS1|2 templates may cause this error when they use constructs like this: |{{#if:{{{2|}}}|title}}={{{2|}}}. When {{{2|}}} does not have a value, the template creates |=.

To resolve this error:

• remove the extra pipe,
• correct the parameter name,
• remove the parameter from the CS1|2 template, or
• change the citation to use a more appropriate template (e.g. change {{Cite document}} to {{Cite web}})

Pages with this error are automatically placed in Category:CS1 errors: empty unknown parameters.^[a]