Sets the filename extension for in-place editing mode to the given String. Each file being edited has this value appended to its filename. The modified file is saved under this new name.
For example:
$ ruby argf.rb file.txt
ARGF.inplace_mode = '.bak'
ARGF.each_line do |line|
print line.sub("foo","bar")
end
Each line of file.txt has the first occurrence of “foo” replaced with “bar”, then the new line is written out to file.txt.bak.
Returns the external encoding for files read from ARGF as an Encoding object. The external encoding is the encoding of the text as stored in a file. Contrast with ARGF.internal_encoding, which is the encoding used to represent this text within Ruby.
To set the external encoding use ARGF.set_encoding.
For example:
ARGF.external_encoding #=> #<Encoding:UTF-8>
If single argument is specified, strings read from ARGF are tagged with the encoding specified.
If two encoding names separated by a colon are given, e.g. “ascii:utf-8”, the read string is converted from the first encoding (external encoding) to the second encoding (internal encoding), then tagged with the second encoding.
If two arguments are specified, they must be encoding objects or encoding names. Again, the first specifies the external encoding; the second specifies the internal encoding.
If the external encoding and the internal encoding are specified, the optional Hash argument can be used to adjust the conversion process. The structure of this hash is explained in the String#encode documentation.
For example:
ARGF.set_encoding('ascii') # Tag the input as US-ASCII text ARGF.set_encoding(Encoding::UTF_8) # Tag the input as UTF-8 text ARGF.set_encoding('utf-8','ascii') # Transcode the input from US-ASCII # to UTF-8.
Returns the String created by generating CSV from ary using the specified options.
Argument ary must be an Array.
Special options:
Option :row_sep defaults to "\n"> on Ruby 3.0 or later and <tt>$INPUT_RECORD_SEPARATOR ($/) otherwise.:
$INPUT_RECORD_SEPARATOR # => "\n"
This method accepts an additional option, :encoding, which sets the base Encoding for the output. This method will try to guess your Encoding from the first non-nil field in row, if possible, but you may need to use this parameter as a backup plan.
For other options, see Options for Generating.
Returns the String generated from an Array:
CSV.generate_line(['foo', '0']) # => "foo,0\n"
Raises an exception if ary is not an Array:
# Raises NoMethodError (undefined method `find' for :foo:Symbol) CSV.generate_line(:foo)
Returns the String created by generating CSV from using the specified options.
Argument rows must be an Array of row. Row is Array of String or CSV::Row.
Special options:
Option :row_sep defaults to "\n" on Ruby 3.0 or later and $INPUT_RECORD_SEPARATOR ($/) otherwise.:
$INPUT_RECORD_SEPARATOR # => "\n"
This method accepts an additional option, :encoding, which sets the base Encoding for the output. This method will try to guess your Encoding from the first non-nil field in row, if possible, but you may need to use this parameter as a backup plan.
For other options, see Options for Generating.
Returns the String generated from an
CSV.generate_lines(['foo', '0'], ['bar', '1'], ['baz', '2']) # => "foo,0\nbar,1\nbaz.2\n"
Raises an exception
# Raises NoMethodError (undefined method `find' for :foo:Symbol) CSV.generate_lines(:foo)
Returns the data created by parsing the first line of string or io using the specified options.
Argument string should be a String object; it will be put into a new StringIO object positioned at the beginning.
Argument io should be an IO object that is:
Open for reading; on return, the IO object will be closed.
Positioned at the beginning. To position at the end, for appending, use method CSV.generate. For any other positioning, pass a preset StringIO object instead.
Argument options: see Options for Parsing
headers Without option headers, returns the first row as a new Array.
These examples assume prior execution of:
string = "foo,0\nbar,1\nbaz,2\n" path = 't.csv' File.write(path, string)
Parse the first line from a String object:
CSV.parse_line(string) # => ["foo", "0"]
Parse the first line from a File object:
File.open(path) do |file| CSV.parse_line(file) # => ["foo", "0"] end # => ["foo", "0"]
Returns nil if the argument is an empty String:
CSV.parse_line('') # => nil
headers With {option headers}, returns the first row as a CSV::Row object.
These examples assume prior execution of:
string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n" path = 't.csv' File.write(path, string)
Parse the first line from a String object:
CSV.parse_line(string, headers: true) # => #<CSV::Row "Name":"foo" "Count":"0">
Parse the first line from a File object:
File.open(path) do |file| CSV.parse_line(file, headers: true) end # => #<CSV::Row "Name":"foo" "Count":"0">
Raises an exception if the argument is nil:
# Raises ArgumentError (Cannot parse nil as CSV): CSV.parse_line(nil)
Returns the Regexp used to identify comment lines; used for parsing; see {Option skip_lines}:
CSV.new('').skip_lines # => nil
Returns the value that determines whether illegal input is to be handled; used for parsing; see {Option liberal_parsing}:
CSV.new('').liberal_parsing? # => false
Returns the encoding of the internal IO object.
Serialization support for the object returned by _getobj_.
Reinitializes delegation from a serialized object.
Creates a new compiler for ERB. See ERB::Compiler.new for details
Returns a string containing the IP address representation in canonical form.
Returns true if the ipaddr is a link-local address. IPv4 addresses in 169.254.0.0/16 reserved by RFC 3927 and Link-Local IPv6 Unicast Addresses in fe80::/10 reserved by RFC 4291 are considered link-local.
Returns true if the ipaddr is an IPv4-mapped IPv6 address.
Returns a new ipaddr built by converting the native IPv4 address into an IPv4-mapped IPv6 address.
Returns a string for DNS reverse lookup compatible with RFC1886.
Set date-time format.
datetime_format
A string suitable for passing to strftime.
Returns the date format being used. See datetime_format=