1
0
Fork 0
mirror of https://github.com/ruby/ruby.git synced 2022-11-09 12:17:21 -05:00
ruby--ruby/doc/string/new.rdoc
Burdette Lamar 7be4d900f0
[DOC] Enhanced RDoc for String (#5751)
Adds to doc for String.new, also making it compliant with documentation_guide.rdoc.
    Fixes some broken links in io.c (that I failed to correct yesterday).
2022-04-02 14:26:49 -05:00

51 lines
1.9 KiB
Text

Returns a new \String that is a copy of +string+.
With no arguments, returns the empty string with the Encoding <tt>ASCII-8BIT</tt>:
s = String.new
s # => ""
s.encoding # => #<Encoding:ASCII-8BIT>
With optional argument +string+ and no keyword arguments,
returns a copy of +string+ with the same encoding:
String.new('foo') # => "foo"
String.new('тест') # => "тест"
String.new('こんにちは') # => "こんにちは"
(Unlike \String.new,
a {string literal}[rdoc-ref:syntax/literals.rdoc@String+Literals] like <tt>''</tt> or a
{here document literal}[rdoc-ref:syntax/literals.rdoc@Here+Document+Literals]
always has {script encoding}[rdoc-ref:encodings.rdoc@Script+Encoding].)
With optional keyword argument +encoding+, returns a copy of +string+
with the specified encoding;
the +encoding+ may be an Encoding object, an encoding name,
or an encoding name alias:
String.new('foo', encoding: Encoding::US_ASCII).encoding # => #<Encoding:US-ASCII>
String.new('foo', encoding: 'US-ASCII').encoding # => #<Encoding:US-ASCII>
String.new('foo', encoding: 'ASCII').encoding # => #<Encoding:US-ASCII>
The given encoding need not be valid for the string's content,
and that validity is not checked:
s = String.new('こんにちは', encoding: 'ascii')
s.valid_encoding? # => false
But the given +encoding+ itself is checked:
String.new('foo', encoding: 'bar') # Raises ArgumentError.
With optional keyword argument +capacity+, returns a copy of +string+
(or an empty string, if +string+ is not given);
the given +capacity+ is advisory only,
and may or may not set the size of the internal buffer,
which may in turn affect performance:
String.new(capacity: 1)
String.new('foo', capacity: 4096)
The +string+, +encoding+, and +capacity+ arguments may all be used together:
String.new('hello', encoding: 'UTF-8', capacity: 25)