The From field inherits from StructuredField and handles the From: header field in the email.
Sending from to a mail message will instantiate a Mail::Field object that has a FromField as its field type. This includes all Mail::CommonAddress module instance metods.
Only one From field can appear in a header, though it can have multiple addresses and groups of addresses.
mail = Mail.new mail.from = 'Mikel Lindsaar <mikel@test.lindsaar.net>, ada@test.lindsaar.net' mail.from #=> ['mikel@test.lindsaar.net', 'ada@test.lindsaar.net'] mail[:from] #=> '#<Mail::Field:0x180e5e8 @field=#<Mail::FromField:0x180e1c4 mail['from'] #=> '#<Mail::Field:0x180e5e8 @field=#<Mail::FromField:0x180e1c4 mail['From'] #=> '#<Mail::Field:0x180e5e8 @field=#<Mail::FromField:0x180e1c4 mail[:from].encoded #=> 'from: Mikel Lindsaar <mikel@test.lindsaar.net>, ada@test.lindsaar.net\r\n' mail[:from].decoded #=> 'Mikel Lindsaar <mikel@test.lindsaar.net>, ada@test.lindsaar.net' mail[:from].addresses #=> ['mikel@test.lindsaar.net', 'ada@test.lindsaar.net'] mail[:from].formatted #=> ['Mikel Lindsaar <mikel@test.lindsaar.net>', 'ada@test.lindsaar.net']