The Universe of Discourse

More Uzi-clubbing: a counter­example
Last year I wrote an article about iterating over a hash, searching for a certain key. Larry Wall called said this was like "clubbing someone to death with a loaded Uzi", because the whole point of a hash is that you don't have to scan all the keys to find the one you want.

I ended the article by saying:

I had already realized that you could, in principle, commit this error with a regular array instead of with a hash, but I had never seen an example until...

    ...
    LINE: while ( ( line = in.readLine()) != null ) {
        String[] fields = line.split("\t");  

        ...
        for ( int i = 0; i < fields.length; i++ ) {
            if ( ! isEmpty(fields[i]) ) {
                switch(i) {
                    case 0: citation.setCitationType(fields[i]); break;
                    case 1: setAuthors(citation,fields[i],personHome,false); break;
                    case 2: citation.setPublishYear(Integer.parseInt(fields[i])); break;
                    case 3: citation.setTitle(fields[i]); break;
                    ...
                    case 19: citation.setURL(fields[i]); break;
                    case 20: citation.setDoi(fields[i]); break;
                    default: warn("Empty field expected, found: " + fields[i] + " for line: " + line); break;
                }
            }
        }
    }
    ...

My temptation here was to replace the loop and the switch with code like this:

                    citation.setCitationType(fields[0]);
                    setAuthors(citation,fields[1],personHome,false);
                    citation.setPublishYear(Integer.parseInt(fields[2]));
                    citation.setTitle(fields[3]);
                    ...
                    citation.setURL(fields[19]);
                    citation.setDoi(fields[20]);

		    if (! isEmpty(fields[13])) warn("Empty field expected...");

                    if (! isEmpty(fields[0])) citation.setCitationType(fields[0]);
                    if (! isEmpty(fields[1])) setAuthors(citation,fields[1],personHome,false);
                    if (! isEmpty(fields[2])) citation.setPublishYear(Integer.parseInt(fields[2]));
                    if (! isEmpty(fields[3])) citation.setTitle(fields[3]);
                    ...
		    if (! isEmpty(fields[13])) warn("Empty field expected...");
                    ...
                    if (! isEmpty(fields[19])) citation.setURL(fields[19]);
                    if (! isEmpty(fields[20])) citation.setDoi(fields[20]);

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