Time from core 2.3.0 vs from stdlib 2.5.3












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I'm a little confused with Ruby documentation on https://ruby-doc.org/. We can find there Time class as a part of core 2.3.0, where we have 60 functions described, and also Time class as a part of stdlib 2.5.3, where we have only 13. Does these descriptions describe the same class? Are both actual for Ruby 2.5.3? Which of these descriptions should I trust?






ruby







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  • 1




    The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
    – Stefan
    Nov 19 '18 at 16:45






  • 1




    Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
    – Stefan
    Nov 19 '18 at 16:48
















0














I'm a little confused with Ruby documentation on https://ruby-doc.org/. We can find there Time class as a part of core 2.3.0, where we have 60 functions described, and also Time class as a part of stdlib 2.5.3, where we have only 13. Does these descriptions describe the same class? Are both actual for Ruby 2.5.3? Which of these descriptions should I trust?






ruby







share|improve this question


















  • 1




    The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
    – Stefan
    Nov 19 '18 at 16:45






  • 1




    Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
    – Stefan
    Nov 19 '18 at 16:48














0












0








0







I'm a little confused with Ruby documentation on https://ruby-doc.org/. We can find there Time class as a part of core 2.3.0, where we have 60 functions described, and also Time class as a part of stdlib 2.5.3, where we have only 13. Does these descriptions describe the same class? Are both actual for Ruby 2.5.3? Which of these descriptions should I trust?






ruby







share|improve this question













I'm a little confused with Ruby documentation on https://ruby-doc.org/. We can find there Time class as a part of core 2.3.0, where we have 60 functions described, and also Time class as a part of stdlib 2.5.3, where we have only 13. Does these descriptions describe the same class? Are both actual for Ruby 2.5.3? Which of these descriptions should I trust?






ruby




ruby






share|improve this question













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asked Nov 19 '18 at 16:34









Karol Selak

1,26611332




1,26611332








  • 1




    The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
    – Stefan
    Nov 19 '18 at 16:45






  • 1




    Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
    – Stefan
    Nov 19 '18 at 16:48














  • 1




    The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
    – Stefan
    Nov 19 '18 at 16:45






  • 1




    Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
    – Stefan
    Nov 19 '18 at 16:48








1




1




The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
– Stefan
Nov 19 '18 at 16:45




The docs from stdlib are pretty clear: "When 'time' is required, Time is extended with additional methods for parsing and converting Times.". So yes, these are two different things: the core Time class and some add-ons from stdlib.
– Stefan
Nov 19 '18 at 16:45




1




1




Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
– Stefan
Nov 19 '18 at 16:48




Regarding the two versions: ruby-doc.org hosts docs for several Ruby versions. You should probably use the one matching your Ruby version.
– Stefan
Nov 19 '18 at 16:48












1 Answer
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There is both a core Time library and a stdlib Time library.



Core one implements the core functionality of Time. Its structures, basic math, time zones, and generic formatting functions. Stdlib adds additional convenience methods for parsing and formatting.



I can only guess why from my own experience with dates and times. There are a lot of date and time formats and they can rapidly bloat out an otherwise simple library both for memory and complexity. I presume the Ruby folks wanted to keep core Time simple and made the extra formatting optional.



Time does have a few formatting functions like asctime, ctime, and strftime. These you get for free from C, and strftime is quite powerful.






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  • It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
    – tadman
    Nov 19 '18 at 17:29











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1 Answer
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There is both a core Time library and a stdlib Time library.



Core one implements the core functionality of Time. Its structures, basic math, time zones, and generic formatting functions. Stdlib adds additional convenience methods for parsing and formatting.



I can only guess why from my own experience with dates and times. There are a lot of date and time formats and they can rapidly bloat out an otherwise simple library both for memory and complexity. I presume the Ruby folks wanted to keep core Time simple and made the extra formatting optional.



Time does have a few formatting functions like asctime, ctime, and strftime. These you get for free from C, and strftime is quite powerful.






share|improve this answer





















  • It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
    – tadman
    Nov 19 '18 at 17:29
















2














There is both a core Time library and a stdlib Time library.



Core one implements the core functionality of Time. Its structures, basic math, time zones, and generic formatting functions. Stdlib adds additional convenience methods for parsing and formatting.



I can only guess why from my own experience with dates and times. There are a lot of date and time formats and they can rapidly bloat out an otherwise simple library both for memory and complexity. I presume the Ruby folks wanted to keep core Time simple and made the extra formatting optional.



Time does have a few formatting functions like asctime, ctime, and strftime. These you get for free from C, and strftime is quite powerful.






share|improve this answer





















  • It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
    – tadman
    Nov 19 '18 at 17:29














2












2








2






There is both a core Time library and a stdlib Time library.



Core one implements the core functionality of Time. Its structures, basic math, time zones, and generic formatting functions. Stdlib adds additional convenience methods for parsing and formatting.



I can only guess why from my own experience with dates and times. There are a lot of date and time formats and they can rapidly bloat out an otherwise simple library both for memory and complexity. I presume the Ruby folks wanted to keep core Time simple and made the extra formatting optional.



Time does have a few formatting functions like asctime, ctime, and strftime. These you get for free from C, and strftime is quite powerful.






share|improve this answer












There is both a core Time library and a stdlib Time library.



Core one implements the core functionality of Time. Its structures, basic math, time zones, and generic formatting functions. Stdlib adds additional convenience methods for parsing and formatting.



I can only guess why from my own experience with dates and times. There are a lot of date and time formats and they can rapidly bloat out an otherwise simple library both for memory and complexity. I presume the Ruby folks wanted to keep core Time simple and made the extra formatting optional.



Time does have a few formatting functions like asctime, ctime, and strftime. These you get for free from C, and strftime is quite powerful.







share|improve this answer












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answered Nov 19 '18 at 17:01









Schwern

88.4k16101229




88.4k16101229












  • It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
    – tadman
    Nov 19 '18 at 17:29


















  • It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
    – tadman
    Nov 19 '18 at 17:29
















It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
– tadman
Nov 19 '18 at 17:29




It is really odd that Time exists by default and require 'time' adds more methods to Time, but that's how it is.
– tadman
Nov 19 '18 at 17:29


















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