Ruby How to Convert String to Symbol Easily

In Ruby, convert a string to a symbol by calling to_sym on the string, like "example".to_sym.

Examples

Input"hello"

Output:hello

Input"user_name"

Output:user_name

Input"123abc"

Output:"123abc"

How to Think About It

To convert a string to a symbol, think of symbols as names or labels that Ruby uses internally. You take the string and tell Ruby to treat it as a symbol by using the to_sym method, which changes the string into a symbol form.

Algorithm

1

Get the input string.

2

Call the <code>to_sym</code> method on the string.

3

Return the resulting symbol.

Code

ruby

str = "example"
sym = str.to_sym
puts sym

Output

example

Dry Run

Let's trace converting the string "example" to a symbol.

1

Start with string

str = "example"

2

Convert to symbol

sym = str.to_sym # sym becomes :example

3

Print symbol

puts sym # outputs example

Variable	Value
str	"example"
sym	:example

Why This Works

Step 1: What is a symbol?

A symbol is a lightweight, immutable identifier often used as names or keys in Ruby.

Step 2: Using to_sym method

The to_sym method converts a string into its symbol equivalent.

Step 3: Why convert?

Symbols are faster and use less memory than strings when used repeatedly as identifiers.

Alternative Approaches

intern

ruby

"example".intern

The <code>intern</code> method is an alias for <code>to_sym</code>, so it works the same way.

Complexity: O(1) time, O(1) space

Time Complexity

Converting a string to a symbol is a constant time operation because it just creates or references a symbol.

Space Complexity

It uses constant space since symbols are stored once and reused.

Which Approach is Fastest?

Both to_sym and intern are equally fast since they do the same thing.

Approach	Time	Space	Best For
to_sym	O(1)	O(1)	Clear and common method
intern	O(1)	O(1)	Alias of to_sym, same performance