Parse Excel data raises "File error" - excel

Question

I have three functions in a Perl script to parse an Excel file to getthe desired output Excel file. I achieved the correct output, however I get an error
File error: data may have been lost
Likely the root cause is writing over the same Excel cell twice in the file.
How do I get rid of this error while maintaining the functions in the script?
Input file
A B
Apples Carrots
Oranges Broccoli
Grapes Spinach
Desire output file
A B
Apples Carrots
Oranges Broccoli
PEACHES ASPARAGUS
Perl code
use v5.10.0;
use warnings;
use Spreadsheet::ParseExcel;
use Spreadsheet::ParseExcel::SaveParser;
use Spreadsheet::WriteExcel;
my $parser = Spreadsheet::ParseExcel::SaveParser->new();
my $workbook_R = $parser->parse('C:\Perl\databases\Fruits_and_Veggies.xls');
my $workbook_W = Spreadsheet::WriteExcel->new('C:\Perl\databases\New_Fruits_and_Veggies.xls');
my $worksheet_W = $workbook_W->add_worksheet();
for our $worksheet_R ( $workbook_R->worksheets() ) {
my ( $row_min, $row_max ) = $worksheet_R->row_range();
my ( $col_min, $col_max ) = $worksheet_R->col_range();
for our $row ( $row_min .. $row_max ) {
for our $col ( $col_min .. $col_max ) {
FruitStand();
VeggieStand();
ComboStand();
#------------------------------------------------------------------------------
# sub FruitStand - parsing: replace Grapes with PEACHES
#------------------------------------------------------------------------------
sub FruitStand {
# if the cell contains Grapes write 'PEACHES' instead
my $cell_grapes = $worksheet_R->get_cell( $row, $col );
if ( $cell_grapes->value() =~ /Grapes/ ) {
$worksheet_W->write($row, $col,"PEACHES");
}
}
#------------------------------------------------------------------------------
# sub VeggieStand - parsing: repalce Spinach with ASPARAGUS
#------------------------------------------------------------------------------
sub VeggieStand {
# if the cell contains Spinach write 'ASPARAGUS' instead
my $cell_veggies = $worksheet_R->get_cell( $row, $col );
# my $cell = $worksheet_R->get_cell( $row, $col );
if (/ $cell_veggies->value() =~ /Spinach/ ) {
$worksheet_W->write($row, $col,"ASPARAGUS");
}
}
#------------------------------------------------------------------------------
# Writing all fruits and veggies with the 2 changes (PEACHES and ASPARAGUS)
#------------------------------------------------------------------------------
sub ComboStand {
my $cell = $worksheet_R->get_cell( $row, $col );
$worksheet_W->write($row, $col, $cell->value()) ;
}
}
}
}

Answer 1

As you have said, the error message is due to a cell being written several times. You can get rid of the error message by ensuring that each cell is only written once. Since your three subroutines have very similar functionality, they can be combined into a single set of lines that does everything, and use an if / else cascade to decide which action should be taken.
for our $row ( $row_min .. $row_max ) {
for our $col ( $col_min .. $col_max ) {
my $cell = $worksheet_R->get_cell( $row, $col );
if($cell->value() =~ /Spinach/) {
$worksheet_W->write($row, $col,"ASPARAGUS");
}
elsif($cell->value() =~ /Grapes/) {
$worksheet_W->write($row, $col,"PEACHES");
}
else {
$worksheet_W->write($row, $col, $cell->value()) ;
}
}
}
If you have to keep the functions, I suggest something like this, where you have a function that takes the current cell and applies any appropriate transformations to it, and returns the text ready for output. This keeps the repetition of reading the cell and writing the cell out of the subroutines:
for our $row ( $row_min .. $row_max ) {
for our $col ( $col_min .. $col_max ) {
my $cell = $worksheet_R->get_cell( $row, $col );
$worksheet_w->write( $row, $col, produce_check($cell->value) );
}
}
And the produce_check sub that performs the swaps would also be a good place to do any text normalisations or other checks you might want to do on the input, e.g. removing extra whitespace, setting all the output to title case, etc.
sub produce_check {
my $prod = shift;
# maybe we have to make sure there's no trailing whitespace on $prod
$prod =~ s/\s*$//;
my %swaps = (
grapes => 'peaches',
spinach => 'asparagus',
tins => 'cans',
zuchini => 'zucchini'
);
# is $prod one of pieces of produce we have to swap?
# perhaps our input is in a mixture of cases, uppercase, lowercase, titlecase
# to avoid having to add all those variations to the %swaps hash, we convert
# to lowercase using `lc`
if ( $swaps{ lc($prod) } ) {
$prod = $swaps{ lc($prod) };
}
# this line uses `ucfirst($prod)` to convert all output to titlecase.
# You could also convert everything to lowercase ( `lc($prod)` ), to
# uppercase ( `uc($prod)` ), or just leave it as-is by using `return $prod;`
return ucfirst( $prod );
}