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Subject: Section 4 Types: TBD: Should "blank" also be a possible value result?
Hi, Section "4 Types" has | TBD: Should "blank" also be a possible value result? This is needed for | empty parameters; it can also occur with an intersection of | non-overlapping references. For the moment, presume that it's a kind | of reference (a reference with no cells as content). But are they | distinguishable? And what is the type of an empty cell? Empty is | distinguishable from a zero-length Text value, because COUNTA makes this | distinction. Actually we need both and have to distinguish between an "empty cell" and a "no cell" as in the intersection case. A "no cell" intersection is a reference error. An "empty cell" return value for example is needed in [HV]LOOKUP results, where for an empty cell the expression ISBLANK(LOOKUP(...)) must yield TRUE (OOo doesn't implement that yet). An "empty cell" value is undetermined until evaluated, which is needed in comparisons where with an empty cell A1 (or a LOOKUP result) both expressions IF(A1=0) and IF(A1="") yield TRUE. An empty cell passed as parameter will never be the same as an omitted parameter, at least to my knowledge. Any other observations? Eike -- Automatic string conversions considered dangerous. They are the GOTO statements of spreadsheets. --Robert Weir on the OpenDocument formula subcommittee's list.