如何更改提示

IRB.conf[:DEFAULT]

# Shows current directory
Ripl.config[:prompt] = lambda { Dir.pwd + \'> \' }
# Print current line number
Ripl.config[:prompt] = lambda { \"ripl(#{Ripl.shell.line})> \" }
# Simple string prommpt
Ripl.config[:prompt] = \'>>> \'

>> Ripl.shell.prompt = lambda { Dir.pwd + \'> \' }