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Well, "1.WHAT.say" is also available. But Perl 6 is designed to put code smells in capital letters. EVAL, for example. WHAT shouldn't be used in normal code,

by labster 11y ago

Well, "1.WHAT.say" is also available. But Perl 6 is designed to put code smells in capital letters. EVAL, for example. WHAT shouldn't be used in normal code, but it's useful as a teaching tool or for debugging. If you want to test if something is an integer, you'll want "1 ~~ Int" instead.

logicallee 11y ago
Let me get this straight - the first example in the tutorial is code that you shouldn't write. Got it. By the way guys, string concatenation isn't . or + or a comma or something. It's a tilde: ~ 'a' ~ 'b' to get 'ab'. Because it looks like a "piece of string" ... that ties ... strings together, apparently.
- SamReidHughes 11y ago
  Getting the type of a value is useful to beginners and belongs in a tutorial. The one time I tried Perl 6 was a few weeks ago, and it took a while to find out how to do this exact thing.
  - tomjakubowski 11y ago
    But Perl is unityped so I don't think it'd be useful there. :V
    - raiph 11y ago
      That's gotta be a joke but I'm missing it -- can you spare a hint?
      - tomjakubowski 11y ago
        https://existentialtype.wordpress.com/2011/03/19/dynamic-languages-are-static-languages/ https://existentialtype.wordpress.com/2011/03/19/dynamic-lan...
        raiph 11y ago
        The article you've linked is about unityped languages. Perl 6 is not unityped. To quote the conclusion of the article you linked: > Why should you care? Because, I argue, that a fully expressive language is one that supports the delicate interplay between static and dynamic techniques. Languages that force only one perspective on you ... hobble you; languages that admit both modes of reasoning enable you and liberate you from the tyranny of a single type. It would seem he ought to love Perl 6. "Getting beyond static vs dynamic" may be of interest: * HN discussion https://news.ycombinator.com/item?id=9089259 https://news.ycombinator.com/item?id=9089259 * Youtube: https://www.youtube.com/watch?v=id4pDstMu1s https://www.youtube.com/watch?v=id4pDstMu1s
- sparky_z 11y ago
  That's because . is a method call, + is addition, and comma is a list separator. Which of those would you give up? So yes, the ~ is a little unique to Perl6, but at least they were thoughtful enough to pick something with more than one easy mnemonic. I guarantee you, most people new to the language would be much more put-off by keeping perl5's -> for method calls. Perl lost that battle, it's over. They're making the best of it. Also, any language with a self-reflective object system is going to show that off to beginners to help them explore, even if it wouldn't be used in production code much. That's like complaining about a language tutorial showing off the REPL to start out, even though you don't use it in production code.
- kbenson 11y ago
  > Let me get this straight - the first example in the tutorial is code that you shouldn't write. Got it. If you read a little farther you might have seen this: Note: .VAR and .WHAT are code smells. They’re useful to understand the language and debug, but testing against what they return is nearly always the wrong approach. > Because it looks like a "piece of string" ... that ties ... strings together, apparently. You're mistaking a mnemonic for the reasoning. The reasoning is most likely because using a period for string concatenation is likely to cause problems when it's also used for method calls and strings can have methods, and when methods can be quotes. E.g. "foo"."chars"(), which might be useful with string interpolation. As for why it's not +, that's covered as well. Perl takes the stance that operators should be different for different operation types. What does foo + bar mean in python? You need to know the types of foo and bar to know that. In Perl 5 and Perl 6, you know whether you are adding numeric types or concatenating (not adding) strings. It's easy to assume no thought went into the development[1], but it's been very well thought out and been baking for a very long time. They spent that time actually testing their ideas, and making changes when reality didn't match expectations. 1: for that matter, a lot of people think that about Perl 5, which is untrue, it just has different design goals than many languages
  - singingfish 11y ago
    I have two trite one-liners about perl(5) in comparison and to other languages these days. 1. Python helps you think more like the computer does. Perl helps the computer think more like you. 2. Modern Perl is C# for hippies.
    - raiph 11y ago
      Have you seen https://www.youtube.com/watch?v=JpqnNCx7wVY https://www.youtube.com/watch?v=JpqnNCx7wVY?
- enqk 11y ago
  the use of + for string concatenation is not exactly compelling either, since string concatenation, unlike addition, is not commutative
- Ulti 11y ago
  Yeah because we can't possibly have languages which diverge in syntax... I mean I don't use any languages every day where the concat operator is || for example which is short circuit OR for most people. cough PgSQL cough JavaScript overloading + to mean addition and string concatenation was the worst decision ever given the use case of JS. 1 + '1' * 1 is not the same as '1' + 1 * 1 good job. That definitely wont be evil once the values are in a more complex equation with variables coming from some server side JSON string... at all. Definitely wont lead to any unusual bugs when something like the following happens 1 + '000001'. You might not notice 2 being 12 for a while but your customer will likely notice 2 suddenly becoming 1000001. At least '~' joins two different string together when writing. Makes a lot more sense than '+' to me ~ Ulti 2015

by labster 11y ago

logicallee 11y ago

Let me get this straight - the first example in the tutorial is code that you shouldn't write. Got it. By the way guys, string concatenation isn't . or + or a comma or something. It's a tilde: ~ 'a' ~ 'b' to get 'ab'. Because it looks like a "piece of string" ... that ties ... strings together, apparently.

SamReidHughes 11y ago
Getting the type of a value is useful to beginners and belongs in a tutorial. The one time I tried Perl 6 was a few weeks ago, and it took a while to find out how to do this exact thing.
- tomjakubowski 11y ago
  But Perl is unityped so I don't think it'd be useful there. :V
  - raiph 11y ago
    That's gotta be a joke but I'm missing it -- can you spare a hint?
    - tomjakubowski 11y ago
      https://existentialtype.wordpress.com/2011/03/19/dynamic-languages-are-static-languages/ https://existentialtype.wordpress.com/2011/03/19/dynamic-lan...
      - raiph 11y ago
        The article you've linked is about unityped languages. Perl 6 is not unityped. To quote the conclusion of the article you linked: > Why should you care? Because, I argue, that a fully expressive language is one that supports the delicate interplay between static and dynamic techniques. Languages that force only one perspective on you ... hobble you; languages that admit both modes of reasoning enable you and liberate you from the tyranny of a single type. It would seem he ought to love Perl 6. "Getting beyond static vs dynamic" may be of interest: * HN discussion https://news.ycombinator.com/item?id=9089259 https://news.ycombinator.com/item?id=9089259 * Youtube: https://www.youtube.com/watch?v=id4pDstMu1s https://www.youtube.com/watch?v=id4pDstMu1s
sparky_z 11y ago
That's because . is a method call, + is addition, and comma is a list separator. Which of those would you give up? So yes, the ~ is a little unique to Perl6, but at least they were thoughtful enough to pick something with more than one easy mnemonic. I guarantee you, most people new to the language would be much more put-off by keeping perl5's -> for method calls. Perl lost that battle, it's over. They're making the best of it. Also, any language with a self-reflective object system is going to show that off to beginners to help them explore, even if it wouldn't be used in production code much. That's like complaining about a language tutorial showing off the REPL to start out, even though you don't use it in production code.
kbenson 11y ago
> Let me get this straight - the first example in the tutorial is code that you shouldn't write. Got it. If you read a little farther you might have seen this: Note: .VAR and .WHAT are code smells. They’re useful to understand the language and debug, but testing against what they return is nearly always the wrong approach. > Because it looks like a "piece of string" ... that ties ... strings together, apparently. You're mistaking a mnemonic for the reasoning. The reasoning is most likely because using a period for string concatenation is likely to cause problems when it's also used for method calls and strings can have methods, and when methods can be quotes. E.g. "foo"."chars"(), which might be useful with string interpolation. As for why it's not +, that's covered as well. Perl takes the stance that operators should be different for different operation types. What does foo + bar mean in python? You need to know the types of foo and bar to know that. In Perl 5 and Perl 6, you know whether you are adding numeric types or concatenating (not adding) strings. It's easy to assume no thought went into the development[1], but it's been very well thought out and been baking for a very long time. They spent that time actually testing their ideas, and making changes when reality didn't match expectations. 1: for that matter, a lot of people think that about Perl 5, which is untrue, it just has different design goals than many languages
- singingfish 11y ago
  I have two trite one-liners about perl(5) in comparison and to other languages these days. 1. Python helps you think more like the computer does. Perl helps the computer think more like you. 2. Modern Perl is C# for hippies.
  - raiph 11y ago
    Have you seen https://www.youtube.com/watch?v=JpqnNCx7wVY https://www.youtube.com/watch?v=JpqnNCx7wVY?
enqk 11y ago
the use of + for string concatenation is not exactly compelling either, since string concatenation, unlike addition, is not commutative
Ulti 11y ago
Yeah because we can't possibly have languages which diverge in syntax... I mean I don't use any languages every day where the concat operator is || for example which is short circuit OR for most people. cough PgSQL cough JavaScript overloading + to mean addition and string concatenation was the worst decision ever given the use case of JS. 1 + '1' * 1 is not the same as '1' + 1 * 1 good job. That definitely wont be evil once the values are in a more complex equation with variables coming from some server side JSON string... at all. Definitely wont lead to any unusual bugs when something like the following happens 1 + '000001'. You might not notice 2 being 12 for a while but your customer will likely notice 2 suddenly becoming 1000001. At least '~' joins two different string together when writing. Makes a lot more sense than '+' to me ~ Ulti 2015