Kernel#chomp

str.chomp([separator]) -> string

chomp and chop are String methods that remove trailing characters. The key difference: chomp removes the record separator (typically newline), while chop unconditionally removes the last character.

Syntax

string.chomp(separator=$/)
string.chop

Parameters

Parameter	Type	Default	Description
separator	String	$/ (input record separator)	The string to remove from the end. Typically \n for newlines.

Examples

Basic usage with chomp

text = "hello world\n"
text.chomp
# => "hello world"

# Without newline, chomp returns a copy
text = "hello world"
text.chomp
# => "hello world"

Using chomp with custom separator

# Remove trailing slashes
path = "/usr/local/bin/"
path.chomp("/")
# => "/usr/local/bin"

# Remove multiple characters
data = "record1|record2|"
data.chomp("|")
# => "record1|record2"

Using chop

text = "hello"
text.chop
# => "hell"

# chop always removes one character
text = "hello\n"
text.chop
# => "hello"

Multiple consecutive removals

text = "hello world\n\n"
text.chomp
# => "hello world\n"

# Use chomp! (mutating version) for multiple passes
text = "hello world\n\n"
text.chomp!
text.chomp!
# => "hello world"

Common Patterns

Reading lines from a file

# Each line read by gets includes newline; chomp removes it
File.readlines("file.txt").each do |line|
  process(line.chomp)
end

# Or more concisely with chomp:
File.each_line("file.txt") { |line| process(line.chomp) }

Removing trailing whitespace

# chomp only removes the separator, not all whitespace
text = "hello world   \n"
text.chomp
# => "hello world   "

# For all trailing whitespace, use strip:
text.strip
# => "hello world"

Building command strings

# Common pattern: build command, ensure no trailing separator
commands = ["git add .", "git commit -m 'fix'", "git push"]
command = commands.join(" && ").chomp(" && ")
# => "git add . && git commit -m 'fix' && git push"

chomp vs chop

Method	Removes	Use case
chomp	Record separator (usually \n)	Processing file input, user input
chop	Last character unconditionally	Removing trailing newlines regardless of OS

See Also

• Kernel#caller
• Kernel#local_variables
• Kernel#eval