Using OR patterns in shell wildcards

Question

I have the following seperation of logic in my application, as you can see I have a class called SimpleController which is what I use to Import and Find SimpleEntities.

I read all the SimpleEntities into memory List cause I search these Entities very often and its a lot faster then reading from the database everytime I want to search for an Entity.

Would it be better to move the logic where I read and store the SimpleEntities into memory into the SimpleLogic class instead of the SimpleController class?

public class SimpleEntity
{
    public int SimpleId { get; set; }
    public string SimpleName { get; set; }
}

public class SimpleDAL
{
    public ICollection<SimpleEntity> GetAllSimpleEntities()
    {
        //Retrieve SimpleEntities from Database
    }   
    public void InsertSimpleEntity(SimpleEntity simpleEntity)
    {
        //Insert simple Entity into Database
    }
}

public class SimpleLogic
{
    private readonly SimpleDAL simpleDAL = new SimpleDAL();

    public ICollection<SimpleEntity> GetAllSimpleEntities()
    {
        return simpleDAL.GetAllSimpleEntities();
    }
    public void InsertSimpleEntity(SimpleEntity simpleEntity)
    {
        //Validate simpleEntity before adding to database
        if (simpleEntity.SimpleId <= 0)
            throw new  Exception("Invalid SimpleEntity Id: " + simpleEntity.SimpleId);

        if (String.IsNullOrEmpty(simpleEntity.SimpleName))
            throw new Exception("SimpleEntity Name cannot be empty or null");

        simpleDAL.InsertSimpleEntity(simpleEntity);
    }
}

public class SimpleController
{
    private readonly SimpleLogic simpleLogic = new SimpleLogic();
    private List<SimpleEntity> simpleEntities;

    public SimpleController()
    {
        simpleEntities = simpleLogic.GetAllSimpleEntities().ToList();
    }

    public int FindSimpleIndex(int simpleId)
    {
        return simpleEntities.FindIndex(p=> p.SimpleId == simpleId);
    }

    public void ImportOtherSimpleEntity(OtherSimpleEntity otherSimpleEntity)
    {
        if (otherSimpleEntity.Operation == "Update")
        {
            int index = FindSimpleIndex(otherSimpleEntity.OtherSimpleId);
            //If entity was found update SimpleEntity
            if (index > -1)
            {
                //Call SimpleLogic.UpdateSimpleEntity(Pass in SimpleEntity);
            }
        }
    }
}

Solution 1

You don't even need extended globbing enabled to do what you want. This will work in bash:

ls {day*,night*}

Solution 2

There is no option in ls to filter on filename but in most of the shells there are globbing extension man bash /Pattern Matching

ksh

ls -lrtd -- *@(day|night)*

zsh

setopt extendedglob
ls -lrtd -- *(day|night)*

or:

setopt kshglob
ls -lrtd -- *@(day|night)*

bash

shopt -s extglob
ls -lrtd -- *@(day|night)*

In any of these three shells you can do this, but note that if one of the cases doesn't match any file, that pattern will be left unexpanded (e.g. *day* night1.txt othernight.txt if there is no file name containing day; see man bash /EXPANSION or /Brace Expansion specifically):

ls -lrtd -- *{day,night}*

In any shells you can do:

ls -lrtd -- *day* *night*

In zsh, if there's either no day or night file, the last two commands will fail; set the nonomatch or csh_null_glob option, or add (N) after each pattern to avoid this.

Solution 3

Shells do not uses regular expressions for argument expansion.

You can enable the extended pattern matching by

$ shopt -s extglob

and then

$ ls @(day|night).txt
day.txt   night.txt

See for example the Bash Reference Manual (Pattern Matching)

Comments

[Jethro]

Ok, I agree with the SimpleEntityManager aspect. I also though about moving the Entity Validation Logic into the Entity it'self but then the Logic class doesn't seem to have a real use, it just calls the DAL and seems to be a bit of a waste.

[Random832]

What about *{day,night}*. I'd edit it, but I don't know which shells support it?

[itsbruce]

I was adapting the original poster's text; I thought that was clear. sigh. Text updated. Surely you can see that the mechanism works?

[Izkata]

@Random832 Works in bash, ksh, and zsh (none need extended globbing), but not sh - however, Nahuel's last "all shells" example does work in sh.

[Admin]

Unfortunately, that would also pick up on file entries where e.g. the owning user or group contains day or night, not only the filename.