This method is defined for backward compatibility.
Scans the string until the pattern
is matched. Returns the substring up to and including the end of the match, advancing the scan pointer to that location. If there is no match, nil
is returned.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.scan_until(/1/) # -> "Fri Dec 1" s.pre_match # -> "Fri Dec " s.scan_until(/XYZ/) # -> nil
Advances the scan pointer until pattern
is matched and consumed. Returns the number of bytes advanced, or nil
if no match was found.
Look ahead to match pattern
, and advance the scan pointer to the end of the match. Return the number of characters advanced, or nil
if the match was unsuccessful.
It’s similar to scan_until
, but without returning the intervening string.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.skip_until /12/ # -> 10 s #
This returns the value that scan_until
would return, without advancing the scan pointer. The match register is affected, though.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.check_until /12/ # -> "Fri Dec 12" s.pos # -> 0 s.matched # -> 12
Mnemonic: it “checks” to see whether a scan_until
will return a value.
Returns the size of arguments of the method.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'Workbook') method = WIN32OLE_METHOD.new(tobj, 'SaveAs') puts method.size_params # => 11
Returns major version.
tobj = WIN32OLE_TYPE.new('Microsoft Word 10.0 Object Library', 'Documents') puts tobj.major_version # => 8
Returns minor version.
tobj = WIN32OLE_TYPE.new('Microsoft Word 10.0 Object Library', 'Documents') puts tobj.minor_version # => 2
Returns the type library major version.
tlib = WIN32OLE_TYPELIB.new('Microsoft Excel 9.0 Object Library') puts tlib.major_version # -> 1
Returns the type library minor version.
tlib = WIN32OLE_TYPELIB.new('Microsoft Excel 9.0 Object Library') puts tlib.minor_version # -> 3
If obj
is a Hash object, returns obj
.
Otherwise if obj
responds to :to_hash
, calls obj.to_hash
and returns the result.
Returns nil
if obj
does not respond to :to_hash
Raises an exception unless obj.to_hash
returns a Hash object.
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 value that determines whether unconverted fields are to be available; used for parsing; see {Option unconverted_fields
}:
CSV.new('').unconverted_fields? # => nil
Returns an Array containing header converters; used for parsing; see Header Converters:
CSV.new('').header_converters # => []
Returns the value that determines whether illegal input is to be handled; used for parsing; see {Option liberal_parsing
}:
CSV.new('').liberal_parsing? # => false
The block need not return a String object:
csv = CSV.open(path, headers: true) csv.header_convert {|header, field_info| header.to_sym } table = csv.read table.headers # => [:Name, :Value]
If converter_name
is given, the block is not called:
csv = CSV.open(path, headers: true) csv.header_convert(:downcase) {|header, field_info| fail 'Cannot happen' } table = csv.read table.headers # => ["name", "value"]
Raises a parse-time exception if converter_name
is not the name of a built-in field converter:
csv = CSV.open(path, headers: true) csv.header_convert(:nosuch) # Raises NoMethodError (undefined method `arity' for nil:NilClass) csv.read
Processes fields
with @converters
, or @header_converters
if headers
is passed as true
, returning the converted field set. Any converter that changes the field into something other than a String
halts the pipeline of conversion for that field. This is primarily an efficiency shortcut.
Returns a string for DNS reverse lookup compatible with RFC3172.
Set
date-time format.
datetime_format
A string suitable for passing to strftime
.
Returns the date format being used. See datetime_format=
Returns the factorization of value
.
For an arbitrary integer:
p_1**e_1 * p_2**e_2 * ... * p_n**e_n,
prime_division
returns an array of pairs of integers:
[[p_1, e_1], [p_2, e_2], ..., [p_n, e_n]].
Each pair consists of a prime number – a prime factor – and a natural number – its exponent (multiplicity).
value
An arbitrary integer.
generator
Optional. A pseudo-prime generator. generator
.succ must return the next pseudo-prime number in ascending order. It must generate all prime numbers, but may also generate non-prime numbers, too.
ZeroDivisionError
when value
is zero.
Prime.prime_division(45) #=> [[3, 2], [5, 1]] 3**2 * 5 #=> 45
Ruby tries to load the library named string relative to the requiring file’s path. If the file’s path cannot be determined a LoadError
is raised. If a file is loaded true
is returned and false otherwise.