Class Rowfilter

source code

                   object --+                    
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 base.structure.StructureBase --+                
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                   object --+   |                
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           base.common.Parser --+                
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base.structure.ParseableStructure --+            
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             base.structure.Structure --+        
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                           object --+   |        
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      base.structure.RestrictionMixin --+        
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                   rscdef.procdef.ProcDef --+    
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                       rscdef.procdef.ProcApp --+
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                                               Rowfilter

A generator for rows coming from a grammar.

Rowfilters receive rows (i.e., dictionaries) as yielded by a grammar under the name row. Additionally, the embedding row iterator is available under the name rowIter.

Macros are expanded within the embedding grammar.

The procedure definition *must* result in a generator, i.e., there must be at least one yield; in general, this will typically be a ``yield row``, but a rowfilter may swallow or create as many rows as desired.

If you forget to have a yield in the rowfilter source, you'll get a "NoneType is not iterable" error that's a bit hard to understand.

Here, you can only access whatever comes from the grammar. You can access grammar keys in late parameters as row[key] or, if key is like an identifier, as @key.