3 ms·

>Static and dynamic typing each have their own benefits, I struggle to think of any benefits of dynamic typing on a reasonably sized code-base (e.g. 50k+ LOC).

hellofunk 9y ago
> I struggle to think of any benefits of dynamic typing on a reasonably sized code-base (e.g. 50k+ LOC). And yet, it's done all the time with great results.
lordCarbonFiber 9y ago
Cheap and plentiful dev talent. Grab any random guy (and at these shops it's always guys) off the street and bang you've got a python dev. There's always going to be an agility multiplier so long as VC is flowing and getting an mvp and a high head count is worth more than any kind of sustainable product.
- macspoofing 9y ago
  >Grab any random guy (and at these shops it's always guys) off the street and bang you've got a python dev. I expect any programmer to be able to transfer their skillet to a new programming language - especially when we're talking about mainstream languages with a GC. >There's always going to be an agility multiplier so long as VC is flowing and getting an mvp and a high head count is worth more than any kind of sustainable product. What kind of agility multiplier? Maybe it makes a difference during a hackathon where you have 24 hours to put something together or maybe if you're putting together shell scripts ... but taking something to MVP takes weeks or months - mainstream dynamic languages simply don't have any edge in development speed in those instances.
crdoconnor 9y ago
>I struggle to think of any benefits of dynamic typing on a reasonably sized code-base Being able to define and initialize types at runtime offers more flexibility and it's quicker to develop in. I'm frankly surprised nobody brings it up more often but the prototypical example of "static typing done right" - Haskell - is talked about nearly constantly but when I look for actual software I might use that's written using it.... there's so little it's almost embarrassing. One obscure window manager, one obscure VCS, facebook's spam filter and some tool for converting markup. Given a sprinkling of asserts, a decent linter and a high level of test coverage I don't see much of a benefit to adding static typing.
- macspoofing 9y ago
  >Being able to define and initialize types at runtime offers more flexibility and it's quicker to develop in. Quicker if you're writing shell scripts or a small single-purpose applications. Not quicker if you're adding to a codebase of any significant size.
  - crdoconnor 9y ago
    Decent programmers compose code bases of "significant size" from many small, loosely coupled single purpose applications. Yes, IME it's still quicker. OTOH, if you're using "codebase of significant size" as code for "big ball of mud", static typing certainly helps, but integration tests are the real lifesaver.
    - macspoofing 9y ago
      >OTOH, if you're using "codebase of significant size" as code for "big ball of mud", static typing certainly helps, but integration tests are the real lifesaver No. I mean when the codebase is of a certain size, new features require some thought and planning. Features may span multiple-modules. They may require partial or full rewrites or the refactoring of any number of sub-components to support the new behaviour. This means that you proceed carefully because you may not want to introduce regression bugs. This costs time. At that point, you're not limited by your typing speed as you may be putting in net 10 lines of code a day. There is just no benefit to dynamic typing at that point. Worse for dynamic languages, this is where improved tooling and static type constraints start paying extreme dividends.
      - crdoconnor 9y ago
        >No. I mean when the codebase is of a certain size, new features require some thought and planning. Features may span multiple-modules. They may require partial or full rewrites or the refactoring of any number of sub-components to support the new behaviour. This means that you proceed carefully because you may not want to introduce regression bugs. This costs time. Yes. And all equally true for statically typed languages. Refactoring without tests is easier in a statically typed language, but still stupid. If you assume a decent body of tests, the benefit dissipates quickly. If you prototype faster, as you usually will in a dynamically typed language, your design mistakes cost less. Since in large software systems I tend to find that the two biggest sources of bugs are a) errors in specification and b) poorly designed APIs, not obscure edge case bugs, quicker prototyping helps in large projects too. And, if your design is solid, you can still achieve similar benefits as static typing by "locking down" your boundary code with asserts so that future development that interacts with that boundary code will fail quickly if it interacted with in the wrong way. >At that point, you're not limited by your typing speed as you may be putting in net 10 lines of code a day. There is just no benefit to dynamic typing at that point. This is fallacious. You're never limited by your typing speed in any language at any point. The cost of "extra typing" is cognitive, not a finger speed limitation. The benefit of dynamic typing is more flexibility in the code you write (especially useful for writing frameworks and such) and quicker turnaround when prototyping because you do not have to prespecify as much up front.

hellofunk 9y ago

> I struggle to think of any benefits of dynamic typing on a reasonably sized code-base (e.g. 50k+ LOC). And yet, it's done all the time with great results.

lordCarbonFiber 9y ago

Cheap and plentiful dev talent. Grab any random guy (and at these shops it's always guys) off the street and bang you've got a python dev. There's always going to be an agility multiplier so long as VC is flowing and getting an mvp and a high head count is worth more than any kind of sustainable product.

macspoofing 9y ago
>Grab any random guy (and at these shops it's always guys) off the street and bang you've got a python dev. I expect any programmer to be able to transfer their skillet to a new programming language - especially when we're talking about mainstream languages with a GC. >There's always going to be an agility multiplier so long as VC is flowing and getting an mvp and a high head count is worth more than any kind of sustainable product. What kind of agility multiplier? Maybe it makes a difference during a hackathon where you have 24 hours to put something together or maybe if you're putting together shell scripts ... but taking something to MVP takes weeks or months - mainstream dynamic languages simply don't have any edge in development speed in those instances.

crdoconnor 9y ago

>I struggle to think of any benefits of dynamic typing on a reasonably sized code-base Being able to define and initialize types at runtime offers more flexibility and it's quicker to develop in. I'm frankly surprised nobody brings it up more often but the prototypical example of "static typing done right" - Haskell - is talked about nearly constantly but when I look for actual software I might use that's written using it.... there's so little it's almost embarrassing. One obscure window manager, one obscure VCS, facebook's spam filter and some tool for converting markup. Given a sprinkling of asserts, a decent linter and a high level of test coverage I don't see much of a benefit to adding static typing.

macspoofing 9y ago
>Being able to define and initialize types at runtime offers more flexibility and it's quicker to develop in. Quicker if you're writing shell scripts or a small single-purpose applications. Not quicker if you're adding to a codebase of any significant size.
- crdoconnor 9y ago
  Decent programmers compose code bases of "significant size" from many small, loosely coupled single purpose applications. Yes, IME it's still quicker. OTOH, if you're using "codebase of significant size" as code for "big ball of mud", static typing certainly helps, but integration tests are the real lifesaver.
  - macspoofing 9y ago
    >OTOH, if you're using "codebase of significant size" as code for "big ball of mud", static typing certainly helps, but integration tests are the real lifesaver No. I mean when the codebase is of a certain size, new features require some thought and planning. Features may span multiple-modules. They may require partial or full rewrites or the refactoring of any number of sub-components to support the new behaviour. This means that you proceed carefully because you may not want to introduce regression bugs. This costs time. At that point, you're not limited by your typing speed as you may be putting in net 10 lines of code a day. There is just no benefit to dynamic typing at that point. Worse for dynamic languages, this is where improved tooling and static type constraints start paying extreme dividends.
    - crdoconnor 9y ago
      >No. I mean when the codebase is of a certain size, new features require some thought and planning. Features may span multiple-modules. They may require partial or full rewrites or the refactoring of any number of sub-components to support the new behaviour. This means that you proceed carefully because you may not want to introduce regression bugs. This costs time. Yes. And all equally true for statically typed languages. Refactoring without tests is easier in a statically typed language, but still stupid. If you assume a decent body of tests, the benefit dissipates quickly. If you prototype faster, as you usually will in a dynamically typed language, your design mistakes cost less. Since in large software systems I tend to find that the two biggest sources of bugs are a) errors in specification and b) poorly designed APIs, not obscure edge case bugs, quicker prototyping helps in large projects too. And, if your design is solid, you can still achieve similar benefits as static typing by "locking down" your boundary code with asserts so that future development that interacts with that boundary code will fail quickly if it interacted with in the wrong way. >At that point, you're not limited by your typing speed as you may be putting in net 10 lines of code a day. There is just no benefit to dynamic typing at that point. This is fallacious. You're never limited by your typing speed in any language at any point. The cost of "extra typing" is cognitive, not a finger speed limitation. The benefit of dynamic typing is more flexibility in the code you write (especially useful for writing frameworks and such) and quicker turnaround when prototyping because you do not have to prespecify as much up front.