ruby/doc/csv/options/common/row_sep.rdoc

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====== Option +row_sep+
Specifies the row separator, a \String or the \Symbol <tt>:auto</tt> (see below),
to be used for both parsing and generating.
Default value:
CSV::DEFAULT_OPTIONS.fetch(:row_sep) # => :auto
---
When +row_sep+ is a \String, that \String becomes the row separator.
The String will be transcoded into the data's Encoding before use.
Using <tt>"\n"</tt>:
row_sep = "\n"
str = CSV.generate(row_sep: row_sep) do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0\nbar,1\nbaz,2\n"
ary = CSV.parse(str)
ary # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
Using <tt>|</tt> (pipe):
row_sep = '|'
str = CSV.generate(row_sep: row_sep) do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0|bar,1|baz,2|"
ary = CSV.parse(str, row_sep: row_sep)
ary # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
Using <tt>--</tt> (two hyphens):
row_sep = '--'
str = CSV.generate(row_sep: row_sep) do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0--bar,1--baz,2--"
ary = CSV.parse(str, row_sep: row_sep)
ary # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
Using <tt>''</tt> (empty string):
row_sep = ''
str = CSV.generate(row_sep: row_sep) do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0bar,1baz,2"
ary = CSV.parse(str, row_sep: row_sep)
ary # => [["foo", "0bar", "1baz", "2"]]
---
When +row_sep+ is the \Symbol +:auto+ (the default),
generating uses <tt>"\n"</tt> as the row separator:
str = CSV.generate do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0\nbar,1\nbaz,2\n"
Parsing, on the other hand, invokes auto-discovery of the row separator.
Auto-discovery reads ahead in the data looking for the next <tt>\r\n</tt>, +\n+, or +\r+ sequence.
The sequence will be selected even if it occurs in a quoted field,
assuming that you would have the same line endings there.
Example:
str = CSV.generate do |csv|
csv << [:foo, 0]
csv << [:bar, 1]
csv << [:baz, 2]
end
str # => "foo,0\nbar,1\nbaz,2\n"
ary = CSV.parse(str)
ary # => [["foo", "0"], ["bar", "1"], ["baz", "2"]]
The default <tt>$INPUT_RECORD_SEPARATOR</tt> (<tt>$/</tt>) is used
if any of the following is true:
* None of those sequences is found.
* Data is +ARGF+, +STDIN+, +STDOUT+, or +STDERR+.
* The stream is only available for output.
Obviously, discovery takes a little time. Set manually if speed is important. Also note that IO objects should be opened in binary mode on Windows if this feature will be used as the line-ending translation can cause problems with resetting the document position to where it was before the read ahead.
---
Raises an exception if the given value is not String-convertible:
row_sep = BasicObject.new
# Raises NoMethodError (undefined method `to_s' for #<BasicObject:>)
CSV.generate(ary, row_sep: row_sep)
# Raises NoMethodError (undefined method `to_s' for #<BasicObject:>)
CSV.parse(str, row_sep: row_sep)