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-rw-r--r--doc/syntax/literals.rdoc44
1 files changed, 23 insertions, 21 deletions
diff --git a/doc/syntax/literals.rdoc b/doc/syntax/literals.rdoc
index b663f27816..45d3d90c58 100644
--- a/doc/syntax/literals.rdoc
+++ b/doc/syntax/literals.rdoc
@@ -9,10 +9,10 @@ Literals create objects you can use in your program. Literals include:
* Arrays
* Hashes
* Ranges
-* Regular Expressions
-* Procs
+* Regexps
+* Lambda Procs
-== Booleans and nil
+== Boolean and Nil Literals
+nil+ and +false+ are both false values. +nil+ is sometimes used to indicate
"no value" or "unknown" but evaluates to +false+ in conditional expressions.
@@ -61,7 +61,7 @@ Examples:
All these numbers have the same decimal value, 170. Like integers and floats
you may use an underscore for readability.
-=== Floating-Point Literals
+=== \Float Literals
Floating-point numbers may be written as follows:
@@ -72,35 +72,37 @@ Floating-point numbers may be written as follows:
These numbers have the same value, 12.34. You may use underscores in floating
point numbers as well.
-=== Rational Numbers
+=== \Rational Literals
-Numbers suffixed by +r+ are Rational numbers.
+You can write a Rational number as follows (suffixed +r+):
12r #=> (12/1)
12.3r #=> (123/10)
-Rational numbers are exact, whereas Float numbers are inexact.
+A \Rational number is exact, whereas a \Float number may be inexact.
0.1r + 0.2r #=> (3/10)
0.1 + 0.2 #=> 0.30000000000000004
-=== Complex numbers
+=== \Complex Literals
-Numbers suffixed by +i+ are Complex (or imaginary) numbers.
+You can write a Complex number as follows (suffixed +i+):
1i #=> (0+1i)
1i * 1i #=> (-1+0i)
-Also Rational numbers may be imaginary numbers.
+Also \Rational numbers may be imaginary numbers.
12.3ri #=> (0+(123/10)*i)
-+i+ must be placed after +r+, the opposite is not allowed.
++i+ must be placed after +r+; the opposite is not allowed.
- 12.3ir #=> syntax error
+ 12.3ir #=> Syntax error
== Strings
+=== \String Literals
+
The most common way of writing strings is using <tt>"</tt>:
"This is a string."
@@ -198,7 +200,7 @@ a single codepoint in the script encoding:
?\C-\M-a #=> "\x81", same as above
?あ #=> "あ"
-=== Here Documents (heredocs)
+=== Here Document Literals
If you are writing a large block of text you may use a "here document" or
"heredoc":
@@ -278,7 +280,7 @@ read:
content for heredoc two
TWO
-== Symbols
+== \Symbol Literals
A Symbol represents a name inside the ruby interpreter. See Symbol for more
details on what symbols are and when ruby creates them internally.
@@ -297,7 +299,7 @@ Like strings, a single-quote may be used to disable interpolation:
When creating a Hash, there is a special syntax for referencing a Symbol as
well.
-== Arrays
+== \Array Literals
An array is created using the objects between <tt>[</tt> and <tt>]</tt>:
@@ -310,7 +312,7 @@ You may place expressions inside the array:
See Array for the methods you may use with an array.
-== Hashes
+== \Hash Literals
A hash is created using key-value pairs between <tt>{</tt> and <tt>}</tt>:
@@ -334,7 +336,7 @@ is equal to
See Hash for the methods you may use with a hash.
-== Ranges
+== \Range Literals
A range represents an interval of values. The range may include or exclude
its ending value.
@@ -347,7 +349,7 @@ its ending value.
You may create a range of any object. See the Range documentation for details
on the methods you need to implement.
-== Regular Expressions
+== \Regexp Literals
A regular expression is created using "/":
@@ -365,7 +367,7 @@ characters than a string.
See Regexp for a description of the syntax of regular expressions.
-== Procs
+== Lambda Proc Literals
A lambda proc can be created with <tt>-></tt>:
@@ -379,13 +381,13 @@ You can require arguments for the proc as follows:
This proc will add one to its argument.
-== Percent Strings
+== Percent Literals
Besides <tt>%(...)</tt> which creates a String, the <tt>%</tt> may create
other types of object. As with strings, an uppercase letter allows
interpolation and escaped characters while a lowercase letter disables them.
-These are the types of percent strings in ruby:
+These are the types of percent literals:
<tt>%i</tt> :: Array of Symbols
<tt>%q</tt> :: String