Find a string within a string?

Question

imey OP

Created Nov ’20

Replies 2

Boosts 0

Participants 3

I have this var:

Code Block //genes
var extGene = "ee"
var agoGene = "aa"
var creGene = "crcr"
//genotype
var genotype = extGene + agoGene + creGene

The genotype can appear in different variations like "eeaacrcr", "EeAaCrcr" or "EEAACrCr", but there are a lot more combinations. Sometimes the letters in the genes can appear in random order, for example "Ee" or "eE". I am using this switch statement which is getting too complex:

Code Block switch (extGene, agoGene, creGene) {
                case
                ("EE", "aa", "crcr"),
                ("Ee", "aa", "crcr"),
                    ("eE", "aa", "crcr"):
                basPhenotype = (blackArray.randomElement()!)
                case
                ("ee", "aa", "crcr"),
                ("ee", "Aa", "crcr"),
                    ("ee", "aA", "crcr"),
                ("ee", "AA", "crcr"):
                basPhenotype = (chestnutArray.randomElement()!)
                        
                case
                ("EE", "AA", "crcr"),
                ("Ee", "AA", "crcr"),
                ("eE", "AA", "crcr"),
                ("EE", "Aa", "crcr"),
                ("EE", "aA", "crcr"),
                ("Ee", "Aa", "crcr"),
                    ("eE", "Aa", "crcr"),
                    ("Ee", "aA", "crcr"),
                    ("eE", "aA", "crcr"):
                basPhenotype = (bayArray.randomElement()!)

Instead it would be nice to just search the genotype for single letters, irrespective of what order they are in, maybe something like this

if genotype contains "e" + "E" {
uiImage = image1
}

if genotype contains "ee" {
uiImage = image2
}

Does anyone know of a way to simplify the code?

Answered by OOPer in 646010022

If you define a matching operator as follows:

Code Block extension Array where Element == String {
    static func ~= (pattern: Self, value: String) -> Bool {
        return pattern.contains(value)
    }
}

Then you can write a switch statement like this:

Code Block switch (extGene, agoGene, creGene) {
case (["EE","Ee","eE"], "aa", "crcr"):
    basPhenotype = (blackArray.randomElement()!)
case ("ee", ["AA","Aa","aA","aa"], "crcr"):
    basPhenotype = (chestnutArray.randomElement()!)
case (["EE","Ee","eE"], ["AA","Aa","aA"], "crcr"):
    basPhenotype = (bayArray.randomElement()!)
default:
    break
}

But there may be some better ways if you use your own types (for example, Swift enum) for genes.

Boost

Answer 1

Claude31 OP

Nov ’20

Looks like creGene is only "crcr". Exact ?

So you could ignore it.

There may be other ways to express like

Code Block if genotype.contains ("crcr") {		// Just in case in the future
	if genotype.contains ("aa") && !genotype.contains("ee") { 
		basPhenotype = (blackArray.randomElement()!) 
	} else if genotype.contains("ee") {
		basPhenotype = (chestnutArray.randomElement()!) 
	} else {
		basPhenotype = (bayArray.randomElement()!)
	}
}

But that may be less readable than your switch.

0

Answer 2

OOPer OP

Nov ’20

Accepted Answer

If you define a matching operator as follows:

Code Block extension Array where Element == String {
    static func ~= (pattern: Self, value: String) -> Bool {
        return pattern.contains(value)
    }
}

Then you can write a switch statement like this:

Code Block switch (extGene, agoGene, creGene) {
case (["EE","Ee","eE"], "aa", "crcr"):
    basPhenotype = (blackArray.randomElement()!)
case ("ee", ["AA","Aa","aA","aa"], "crcr"):
    basPhenotype = (chestnutArray.randomElement()!)
case (["EE","Ee","eE"], ["AA","Aa","aA"], "crcr"):
    basPhenotype = (bayArray.randomElement()!)
default:
    break
}

But there may be some better ways if you use your own types (for example, Swift enum) for genes.

0