Equality operator.

Returns true if other is equal to self.

Keys are matched case-insensitive. String values are treated equal to an array values with the same string as single element.

HTTP::Headers{"Foo" => "bar"} == HTTP::Headers{"Foo" => "bar"}   # => true
HTTP::Headers{"Foo" => "bar"} == HTTP::Headers{"foo" => "bar"}   # => true
HTTP::Headers{"Foo" => "bar"} == HTTP::Headers{"Foo" => ["bar"]} # => true
HTTP::Headers{"Foo" => "bar"} == HTTP::Headers{"Foo" => "baz"}   # => false

Adds a header with key and value to the header set. If a header with key already exists in the set, value is appended to the existing header.

require "http/headers"

headers = HTTP::Headers.new
headers.add("Connection", "keep-alive")
headers["Connection"] # => "keep-alive"
headers.add("Connection", "Upgrade")
headers["Connection"] # => "keep-alive,Upgrade"

Returns a shallow copy of this object.

Because Value is a value type, this method returns self, which already involves a shallow copy of this object because value types are passed by value.

Must yield this collection's elements to the block.

Returns true if self does not contain any element.

([] of Int32).empty? # => true
([1]).empty?         # => false
[nil, false].empty?  # => false

• #present? returns the inverse.

See Object#hash(hasher)

Returns if among the headers for key there is some that contains word as a value. The word is expected to match between word boundaries (i.e. non-alphanumeric chars).

require "http/headers"

headers = HTTP::Headers{"Connection" => "keep-alive, Upgrade"}
headers.includes_word?("Connection", "Upgrade") # => true

Appends this struct's name and instance variables names and values to the given IO.

struct Point
  def initialize(@x : Int32, @y : Int32)
  end
end

p1 = Point.new 1, 2
p1.to_s    # "Point(@x=1, @y=2)"
p1.inspect # "Point(@x=1, @y=2)"

Serializes headers according to the HTTP protocol.

Prints a list of HTTP header fields in the format described in RFC 7230 §3.2, with each field terminated by a CRLF sequence ("\r\n").

The serialization does not include a double CRLF sequence at the end.

headers = HTTP::Headers{"foo" => "bar", "baz" => %w[qux qox]}
headers.serialize # => "foo: bar\r\nbaz: qux\r\nbaz: qox\r\n"

Serializes headers according to the HTTP protocol.

Prints a list of HTTP header fields in the format described in RFC 7230 §3.2, with each field terminated by a CRLF sequence ("\r\n").

The serialization does not include a double CRLF sequence at the end.

headers = HTTP::Headers{"foo" => "bar", "baz" => %w[qux qox]}
headers.serialize # => "foo: bar\r\nbaz: qux\r\nbaz: qox\r\n"

Same as #inspect(io).