Aleph | A library for exploring persistent homology | Math library

If I use:

As Robin Zigmond commented, you're confusing the Ord and Enum classes. Ord is what's a superclass of Real, but Enum is what succ belongs to.

Ord does not allow you to enumerate, or otherwise generate any elements of a type, it only allows you to compare given elements. And being able to check whether x < y for two real numbers would seem perfectly straightforward and uncontroversial.^†

By contrast, the Enum class is an absolute mathematical mess. This is not a class for enumerating all values of a type (that would be Universe), rather you should just think of it as the class that can be used for list builders of the form [1, 1.5, .. 9] or ['q'..]. These don't really have any clear mathematical interpretation, they're just useful for writing concise practical code.

It has been argued that Float and Double should not have Enum instances. But IMO those instances are ok in as far as the class itself is ok – not good, but not bad enough to warrant the hassle of replacing it with something new (and braking lots of existing code that makes use of list comprehensions).

^†_{Actually, this is worth some consideration. Unlike x < y, which is generally a perfectly fine thing to check, x==y is actually problematic in some ways, both mathematically for exact reals and practically for floating-point numbers. Speaking constructive-mathematically, all you can do is check in finite time that x < y or x > y, but you can never be sure that two values are equal. And for floating-point numbers, you should never assume that two values are ==-equal even if they come out of mathematically equivalent comparisons. Instead, what you should do in testing is to check that x-ε < y < x+ε for some small ε. (How small is appropriate can be tricky to determine.)}

You need to escape \d in your javascript for it to be equivalent to the C# regex. It should be like this: '^(50|70)(4|5)\\d{9}$'. In your C# code you prefixed the string with a @ which makes this unnecessary there.

If you want these as similar as possible to avoid confusion, you could change your C# pattern to string regex = "^(50|70)(4|5)\\d{9}$";.

Only you will be able to answer your question. The error means that there is already a process that is listining on that port. If you're running a Linux box, use lsof -i (as root or using sudo) to find out which process.

The most likely scenario is that you've run your code already. I.e., you'll find out that a Clojure process is still using that port. And this in turn can easily happen when you forget to stop the server before executing the start-server again. According to the Aleph documentation on start-server, you would need to call .close on the server var.

You ask about the line:

You can use deno upgrade command with specified version for upgrade or downgrade the deno.

You can use unicodedata.normalize to convert code points to their decomposed form, consisting of a base character and a modifier. It doesn't work for all cases (particularly Maqsurah), but could help you write a function to determine some base forms:

Use conditional aggregation:

You can use Sliver widget instead of using ListView.builder. ListVew wideget will build all widget at once, whereas by using Sliver widget you can build widgets when user scroll the screen. Refer the sample code below.