Just trying a very simple thing and it's pretty hard: "Read a CSV file
(raw_data) that has a ; separator so that I can iterate over the lines
and access the fields."
csv_data = raw_data.byLine.joiner("\n")
From the docs, which I find extremly hard to understand:
auto csvReader(Contents = string, Malformed ErrorLevel =
Malformed.throwException, Range, Separator = char)(Range input,
Separator delimiter = ',', Separator quote = '"')
So, let's see if I can decyphre this, step-by-step by trying out:
csv_records = csv_data.csvReader();
Would split the CSV data into iterable CSV records using ',' char as
separator using UFCS syntax. When running this I get:
std.csv.CSVException@/Library/D/dmd/src/phobos/std/csv.d(1283): Row
1's length 0 does not match previous length of 1.
Which indicates some problem because not all fields are set in my CSV
data. So let's ignore any error by specifying Malformed.ignore;
csv_records = csv_data.csvReader(Malformed.ignore);
And now I'm lost (just showing the first candidate):
Error: template std.csv.csvReader cannot deduce function from argument
types !()(Result, Malformed), candidates are:
/Library/D/dmd/src/phobos/std/csv.d(327): csvReader(Contents =
string, Malformed ErrorLevel = Malformed.throwException, Range,
Separator = char)(Range input, Separator delimiter = ',', Separator
quote = '"')
with Contents = string,
ErrorLevel = cast(Malformed)1,
Range = Result,
Separator = Malformed
whose parameters have the following constraints:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
isInputRange!Range
is(Unqual!(ElementType!Range) == dchar)
> isSomeChar!Separator
- !is(Contents T : T[U], U : string)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The docs state Malformed as 2nd parameter, since I use UFCS I assume
that this becomes the first parameter. I don't understand what the 3rd
parameter (Range) is about. 4th parameter is my separator, which I need
to set to ';' somehow.
But from the error message, it looks like DMD tries to use
Malformed.ignore as the 4th (!!) Parameter being the Separator.
I'm totally confused:
* What is used as the 3rd parameter by DMD? Where does it come from?
* How to specify a ';' separator?
This is all pretty confusing...
--
Robert M. Münch
http://www.saphirion.com
smarter | better | faster
