Listing of standard methods
More Classes and Objects example from a Well House Consultants training course
More on More Classes and Objects [link]
Source code: stanley Module: R108
# List of standard methods, and some examples of their use.
widget = Thing.new
can_do = widget.methods
for explain in can_do
# Some testing examples
Sample outputs from that end section
stanley:18: warning: default `to_a' will be obsolete
Standard methods - In Alphabetic order:
"==" - equality / same value
"===" - equality test for case
"=~" - looks like (regular expression)
"__id__" - give me a unique object no.
"class" - what type of object is this? (Yuk!)
"clone" - duplicate object contents (shallow copy?)
"display" - same as to_s but NOT overridden when you override to_s
"dup" - ?? Deep copy
"eql?" - test for identical object
"equal?" - test for one and the same object
"freeze" - makes it read-only from now on (prevents modification)
"frozen?" - Checks if proven
"inspect" - like "p" but returns string, doesn't output it
"instance_of?" - check object type (give class name)
"is_a?" - check object type (unlike class uses inheritance)
Often better that "class" or "instance_of?"
"kind_of?" - same as is_a?
"method" - returns a method object
"methods" - Array of methods
"nil?" - does it point to the nil (false) object?
"private_methods" - selectively lists only private methods
"respond_to?" - check whether a method is there somewhere in the inheritance tree
"send" - call a method named as parameter
thing.send(:setage,25) is equivalent to thing.setage(25)
"singleton_methods" - listing extra methods that apply to this object only
"taint" - mark as "dirty" (so can't be used to open file, for example)
"tainted?" - is it dirty?
"tap" - new in Ruby 1.9; act on object in block but also return object
avoids breaking a pipeline
"to_a" - to array
[default is deprecated]
"to_s" - to string (for printing)
"untaint" - mark it clean! 228c
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