Ruby | Symbol Class

Last Updated : 11 Jul, 2025

The objects of the Symbol class represent the names present inside the Ruby interpreter. They are usually generated by using :name literal syntax or by using to_sym methods. The similar Symbol objects are created for a given name string for the duration of a program's execution, regardless of the content and meaning of the name. Example: Output:

1675428
1675428
1675428

Explanation: If Max is a constant in context1, a method in context2, or class in the context3, then this :Max will be the same object in all given contexts.

Class Method

all_symbols : This method returns an array of symbols that currently present in the Ruby's symbol table.

Symbol.all_symbols

Example: Output:

3250
"
#
$
%
&
'
(
)
*
+
,
-
.
/
:
;
<
=
>
?

Instance Methods

id2name : This method returns a string that is representation of sym.
```
sym.id2name
```
Example: Output:
```
"Geeks"
"Welcome to GeeksforGeeks Portal"
```
inspect : This method return the representation of sym in the form of symbol literal.
```
sym.inspect
```
Example: Output:
```
":geeks"
":\"welcome to geeksforgeeks portal\""
```
to_s : This method is similar to Symbol#id2name. This method returns the name or a string that corresponding to sym.
```
sym.to_s
```
Example: Output:
```
"geeks"
"welcome to geeksforgeeks portal"
```
<=> :It compares sym to other_sym after calling to_s. It returns -1 if sym is less than other_sym, it returns 0 if sym is equal to other_sym, or it returns +1 if sym is greater than other_sym.
```
sym <=> other_sym 
```
Example: Output:
```
-1
0
1
```
== : It returns true if the sym is equal to obj, otherwise it return false.
```
sym== obj
```
Example: Output:
```
false
true
```
[] : This method returns the value of sym.to_s[].
```
sym[idx] --> char 
sym[b, n] --> string
```
capitalize : This method is similar to Symbol#to_s.
```
sym.capitalize
```
casecmp : This method is case-insensitive version of symbol <=$gt;. It will return -1, 0, 1, or nil. It is worked on A-Z/a-z, not on all Unicode. In this method nil is returned when the two symbols have incompatible encodings or if other_sym is not a symbol.
```
sym.casecmp(other)
```
Example: Output:
```
0
1
-1
nil
```
downcase : This method converts upper-case letters in lower-case.
```
sym.downcase
```
Example: Output:
```
:"welcome to geeksforgeeks"
```
length : This method returns the length of the given sym.
```
sym.length
```
Example: Output:
```
8
```
slice : This method is similar to Symbol#to_s. This method provides you character on the given index from the sym .
```
sym.slice(index)
sym.slice(b, n)
```
Example: Output:
```
"K"
"f"
```
swapcase : This method interchange the case of the characters that present in sym. In other words, it converts lower-case into upper-case and upper-case into lower-case.
```
sym.swapcase
```
Example: Output:
```
"welCOME to GEEKSforgeeks"
```
upcase : This method converts lower-case characters into upper-case.
```
sym.upcase
```
Example: Output:
```
"WELCOME TO GEEKSFORGEEKS"
```
to_proc : This method return a Proc object which answer to the given method by sym.
```
sym.to_proc
```
Example: Output:
```
 ["1", "2", "3", "4", "5"]
```
to_sym This method returns a symbol that corresponding to an object. Here sym has been already a symbol, so in this case it returns it.
```
sym.to_sym
```