Problem with deleting file locks in ArcGIS 10

Question

I did not realize that I should have been deleting cursors after accessing attribute tables until today. Up until now I never did this, but I've noticed that there are lots of file locks after my script runs (I presume it was a bad practice on my part to begin with). ArcGIS 10 help tells me that I should use the following code:

# Delete cursor and row objects to remove locks on the data 
# 
del row 
del rows

I'm doing that in the following function:

# calculate areas
def area_calc( shapefile ):
    "calculates geometric properties of each building"      

    # loop through attribute table    
    Rows = ARCPY.UpdateCursor( shapefile ) 

    for row in Rows:

        geom = row.Shape

        polyArea = geom.area
        row.setValue( perimName, 0 )  # set to zero
        polyPerim = geom.length

        row.setValue( areaName, polyArea )   # update area value
        row.setValue( perimName, polyPerim ) # update perimeter value       

        Rows.updateRow(row)   

    # Delete the row and cursor    
    del row 
    del Rows

    ARCPY.AddMessage( 'Area and Perimeter calculated for each polygon' )

However, when I do that I get the following error message:

Traceback (most recent call last):
  File "LoopModuleBuildingAnalysis.py", line 9, in <module>
    import ConstructionMaterialPhase1
  File "D:\Code\AnalysisPhase1.py", line 101
    del row
      ^
SyntaxError: invalid syntax
Press any key to continue . . . 

Any suggestions what I should be doing? Thanks in advance.

Answer 1

Deleting an unbound name will raise NameError, not SyntaxError. The following code, roughly equivalent, runs fine

>>> def foo():
...     for x in range(0, 5):
...         print x
...     
...     del x
... 
>>> foo()
0
1
2
3
4

Check to see that your for block is indented properly and that you don't have any wacky mix of tabs and spaces.