class IRB::Frame

Constants

CALL_STACK_OFFSET: Default number of frames offset
INIT_STACK_TIMES: Default number of stack frames

Public Class Methods

bottom (n = 0)

Convenience method for Frame#bottom

# File lib/irb/frame.rb, line 61
def Frame.bottom(n = 0)
  @backtrace.bottom(n)
end

new ()

Creates a new stack frame

# File lib/irb/frame.rb, line 26
def initialize
  @frames = [TOPLEVEL_BINDING] * INIT_STACK_TIMES
end

sender ()

Returns the binding context of the caller from the last frame initialized

# File lib/irb/frame.rb, line 71
def Frame.sender
  eval "self", @backtrace.top
end

top (n = 0)

Convenience method for Frame#top

# File lib/irb/frame.rb, line 66
def Frame.top(n = 0)
  @backtrace.top(n)
end

Public Instance Methods

bottom (n = 0)

Returns the n number of frames on the call stack from the first frame initialized.

Raises FrameOverflow if there are no frames in the given stack range.

# File lib/irb/frame.rb, line 54
def bottom(n = 0)
  bind = @frames[n]
  fail FrameOverflow unless bind
  bind
end

top (n = 0)

Returns the n number of frames on the call stack from the last frame initialized.

Raises FrameUnderflow if there are no frames in the given stack range.

# File lib/irb/frame.rb, line 44
def top(n = 0)
  bind = @frames[-(n + CALL_STACK_OFFSET)]
  fail FrameUnderflow unless bind
  bind
end

trace_func (event, file, line, id, binding)

Used by Kernel#set_trace_func to register each event in the call stack

# File lib/irb/frame.rb, line 31
def trace_func(event, file, line, id, binding)
  case event
  when 'call', 'class'
    @frames.push binding
  when 'return', 'end'
    @frames.pop
  end
end