Extended maintenance of Ruby 1.9.3 ended on February 23, 2015. Read more
irb interpreter main routine
# File irb.rb, line 98
def initialize(workspace = nil, input_method = nil, output_method = nil)
@context = Context.new(self, workspace, input_method, output_method)
@context.main.extend ExtendCommandBundle
@signal_status = :IN_IRB
@scanner = RubyLex.new
@scanner.exception_on_syntax_error = false
end
# File irb.rb, line 109
def eval_input
@scanner.set_prompt do
|ltype, indent, continue, line_no|
if ltype
f = @context.prompt_s
elsif continue
f = @context.prompt_c
elsif indent > 0
f = @context.prompt_n
else
f = @context.prompt_i
end
f = "" unless f
if @context.prompting?
@context.io.prompt = p = prompt(f, ltype, indent, line_no)
else
@context.io.prompt = p = ""
end
if @context.auto_indent_mode
unless ltype
ind = prompt(@context.prompt_i, ltype, indent, line_no)[/.*\z/].size +
indent * 2 - p.size
ind += 2 if continue
@context.io.prompt = p + " " * ind if ind > 0
end
end
end
@scanner.set_input(@context.io) do
signal_status(:IN_INPUT) do
if l = @context.io.gets
print l if @context.verbose?
else
if @context.ignore_eof? and @context.io.readable_atfer_eof?
l = "\n"
if @context.verbose?
printf "Use \"exit\" to leave %s\n", @context.ap_name
end
else
print "\n"
end
end
l
end
end
@scanner.each_top_level_statement do |line, line_no|
signal_status(:IN_EVAL) do
begin
line.untaint
@context.evaluate(line, line_no)
output_value if @context.echo?
exc = nil
rescue Interrupt => exc
rescue SystemExit, SignalException
raise
rescue Exception => exc
end
if exc
print exc.class, ": ", exc, "\n"
if exc.backtrace[0] =~ /irb(2)?(\/.*|-.*|\.rb)?:/ && exc.class.to_s !~ /^IRB/ &&
!(SyntaxError === exc)
irb_bug = true
else
irb_bug = false
end
messages = []
lasts = []
levels = 0
for m in exc.backtrace
m = @context.workspace.filter_backtrace(m) unless irb_bug
if m
if messages.size < @context.back_trace_limit
messages.push "\tfrom "+m
else
lasts.push "\tfrom "+m
if lasts.size > @context.back_trace_limit
lasts.shift
levels += 1
end
end
end
end
print messages.join("\n"), "\n"
unless lasts.empty?
printf "... %d levels...\n", levels if levels > 0
print lasts.join("\n")
end
print "Maybe IRB bug!\n" if irb_bug
end
if $SAFE > 2
abort "Error: irb does not work for $SAFE level higher than 2"
end
end
end
end
# File irb.rb, line 314
def inspect
ary = []
for iv in instance_variables
case (iv = iv.to_s)
when "@signal_status"
ary.push format("%s=:%s", iv, @signal_status.id2name)
when "@context"
ary.push format("%s=%s", iv, eval(iv).__to_s__)
else
ary.push format("%s=%s", iv, eval(iv))
end
end
format("#<%s: %s>", self.class, ary.join(", "))
end
# File irb.rb, line 310
def output_value
printf @context.return_format, @context.inspect_last_value
end
# File irb.rb, line 279
def prompt(prompt, ltype, indent, line_no)
p = prompt.dup
p.gsub!(/%([0-9]+)?([a-zA-Z])/) do
case $2
when "N"
@context.irb_name
when "m"
@context.main.to_s
when "M"
@context.main.inspect
when "l"
ltype
when "i"
if $1
format("%" + $1 + "d", indent)
else
indent.to_s
end
when "n"
if $1
format("%" + $1 + "d", line_no)
else
line_no.to_s
end
when "%"
"%"
end
end
p
end
# File irb.rb, line 246
def signal_handle
unless @context.ignore_sigint?
print "\nabort!\n" if @context.verbose?
exit
end
case @signal_status
when :IN_INPUT
print "^C\n"
raise RubyLex::TerminateLineInput
when :IN_EVAL
IRB.irb_abort(self)
when :IN_LOAD
IRB.irb_abort(self, LoadAbort)
when :IN_IRB
# ignore
else
# ignore other cases as well
end
end
# File irb.rb, line 267
def signal_status(status)
return yield if @signal_status == :IN_LOAD
signal_status_back = @signal_status
@signal_status = status
begin
yield
ensure
@signal_status = signal_status_back
end
end
# File irb.rb, line 237
def suspend_context(context)
@context, back_context = context, @context
begin
yield back_context
ensure
@context = back_context
end
end
# File irb.rb, line 227
def suspend_input_method(input_method)
back_io = @context.io
@context.instance_eval{@io = input_method}
begin
yield back_io
ensure
@context.instance_eval{@io = back_io}
end
end
# File irb.rb, line 207
def suspend_name(path = nil, name = nil)
@context.irb_path, back_path = path, @context.irb_path if path
@context.irb_name, back_name = name, @context.irb_name if name
begin
yield back_path, back_name
ensure
@context.irb_path = back_path if path
@context.irb_name = back_name if name
end
end
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