diff options
| -rw-r--r-- | doc/string.rb | 1 | ||||
| -rw-r--r-- | rational.c | 47 |
2 files changed, 25 insertions, 23 deletions
diff --git a/doc/string.rb b/doc/string.rb index b3d5886b8d..4304b96aee 100644 --- a/doc/string.rb +++ b/doc/string.rb @@ -402,6 +402,7 @@ # - #to_c: Returns the complex value of leading characters, interpreted as a complex number. # - #to_i: Returns the integer value of leading characters, interpreted as an integer. # - #to_f: Returns the floating-point value of leading characters, interpreted as a floating-point number. +# - #to_r: Returns the rational value of leading characters, interpreted as a rational. # # <em>Strings and Symbols</em> # diff --git a/rational.c b/rational.c index 89e74c328d..28f116580f 100644 --- a/rational.c +++ b/rational.c @@ -2467,31 +2467,32 @@ string_to_r_strict(VALUE self, int raise) /* * call-seq: - * str.to_r -> rational - * - * Returns the result of interpreting leading characters in +str+ - * as a rational. Leading whitespace and extraneous characters - * past the end of a valid number are ignored. - * Digit sequences can be separated by an underscore. - * If there is not a valid number at the start of +str+, - * zero is returned. This method never raises an exception. - * - * ' 2 '.to_r #=> (2/1) - * '300/2'.to_r #=> (150/1) - * '-9.2'.to_r #=> (-46/5) - * '-9.2e2'.to_r #=> (-920/1) - * '1_234_567'.to_r #=> (1234567/1) - * '21 June 09'.to_r #=> (21/1) - * '21/06/09'.to_r #=> (7/2) - * 'BWV 1079'.to_r #=> (0/1) - * - * NOTE: "0.3".to_r isn't the same as 0.3.to_r. The former is - * equivalent to "3/10".to_r, but the latter isn't so. + * str.to_r -> rational * - * "0.3".to_r == 3/10r #=> true - * 0.3.to_r == 3/10r #=> false + * Returns the result of interpreting leading characters in +self+ as a rational value: + * + * '123'.to_r # => (123/1) # Integer literal. + * '300/2'.to_r # => (150/1) # Rational literal. + * '-9.2'.to_r # => (-46/5) # Float literal. + * '-9.2e2'.to_r # => (-920/1) # Float literal. + * + * Ignores leading and trailing whitespace, and trailing non-numeric characters: + * + * ' 2 '.to_r # => (2/1) + * '21-Jun-09'.to_r # => (21/1) + * + * Returns \Rational zero if there are no leading numeric characters. + * + * 'BWV 1079'.to_r # => (0/1) + * + * NOTE: <tt>'0.3'.to_r</tt> is equivalent to <tt>3/10r</tt>, + * but is different from <tt>0.3.to_r</tt>: + * + * '0.3'.to_r # => (3/10) + * 3/10r # => (3/10) + * 0.3.to_r # => (5404319552844595/18014398509481984) * - * See also Kernel#Rational. + * Related: see {Converting to Non-String}[rdoc-ref:String@Converting+to+Non--5CString]. */ static VALUE string_to_r(VALUE self) |