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-rw-r--r--lib/irb/ext/history.rb53
1 files changed, 45 insertions, 8 deletions
diff --git a/lib/irb/ext/history.rb b/lib/irb/ext/history.rb
index 43c3e4d..30e3fb90 100644
--- a/lib/irb/ext/history.rb
+++ b/lib/irb/ext/history.rb
@@ -31,9 +31,12 @@ module IRB # :nodoc:
end
remove_method :eval_history= if method_defined?(:eval_history=)
- # The command result history limit.
+ # The command result history limit. This method is not available until
+ # #eval_history= was called with non-nil value (directly or via
+ # setting <code>IRB.conf[:EVAL_HISTORY]</code> in <code>.irbrc</code>).
attr_reader :eval_history
- # Sets command result history limit.
+ # Sets command result history limit. Default value is set from
+ # <code>IRB.conf[:EVAL_HISTORY]</code>.
#
# +no+ is an Integer or +nil+.
#
@@ -42,6 +45,9 @@ module IRB # :nodoc:
# If +no+ is 0, the number of history items is unlimited.
#
# If +no+ is +nil+, execution result history isn't used (default).
+ #
+ # History values are available via <code>__</code> variable, see
+ # IRB::History.
def eval_history=(no)
if no
if defined?(@eval_history) && @eval_history
@@ -59,20 +65,51 @@ module IRB # :nodoc:
end
end
- class History # :nodoc:
-
- def initialize(size = 16)
+ # Represents history of results of previously evaluated commands.
+ #
+ # Available via <code>__</code> variable, only if <code>IRB.conf[:EVAL_HISTORY]</code>
+ # or <code>IRB::CurrentContext().eval_history</code> is non-nil integer value
+ # (by default it is +nil+).
+ #
+ # Example (in `irb`):
+ #
+ # # Initialize history
+ # IRB::CurrentContext().eval_history = 10
+ # # => 10
+ #
+ # # Perform some commands...
+ # 1 + 2
+ # # => 3
+ # puts 'x'
+ # # x
+ # # => nil
+ # raise RuntimeError
+ # # ...error raised
+ #
+ # # Inspect history (format is "<item number> <evaluated value>":
+ # __
+ # # => 1 10
+ # # 2 3
+ # # 3 nil
+ #
+ # __[1]
+ # # => 10
+ #
+ class History
+
+ def initialize(size = 16) # :nodoc:
@size = size
@contents = []
end
- def size(size)
+ def size(size) # :nodoc:
if size != 0 && size < @size
@contents = @contents[@size - size .. @size]
end
@size = size
end
+ # Get one item of the content (both positive and negative indexes work).
def [](idx)
begin
if idx >= 0
@@ -85,14 +122,14 @@ module IRB # :nodoc:
end
end
- def push(no, val)
+ def push(no, val) # :nodoc:
@contents.push [no, val]
@contents.shift if @size != 0 && @contents.size > @size
end
alias real_inspect inspect
- def inspect
+ def inspect # :nodoc:
if @contents.empty?
return real_inspect
end