Is there a better way of writing this: ``` override fun toString() = StringBuilder("Match...

# codereview

[Ellen Spertus]

Is there a better way of writing this:

override fun toString() =
        StringBuilder("MatchResult(\"").apply {
            append(baseString())
            append("\"")
            append(slotString())
            append(if (parameters.isEmpty()) "" else ", parameters: $parameters")
            append(if (skippedWords == 0) "" else ", skippedWords: $skippedWords")
            append(if (aliasedWords == 0) "" else ", aliasedWords: $aliasedWords")
            append(intentName?.let { ", intentName: $it" } ?: "")
            append(", capturedWords: $capturedWords)")
        }.toString()

[Ellen Spertus]

It looks godawful as one big string interpolation.

[araqnid]

append(if (aliasedWords == 0) "" else ", aliasedWords: $aliasedWords") — those look odd, because appending “” is a no-op

[araqnid]

I think if you pulled those ‘if’s and (and converted the ‘?.let’ to an ‘if’ too) it would look more sane

[araqnid]

also, use the buildString stdlib function to supply the StringBuilder creation and toString()

[araqnid]

but in priciple, building up a string using a builder block on a StringBuilder is pretty normal, imho

[Mike]

Just in case you're not sure what was meant by 'pull thos e 'ifs'',

if(parameters.isNotEmpty) append(", parameters: $parameters)

[Ellen Spertus]

Thanks, everyone. Yeah those if append empty strings were pretty stupid. They were left over from when I put the values in local variables.

[EyeCon]

My attempt at readability. Not tested.

Untitled

[Mike]

I think this is better. Using StringBuilder rather than an Array and then 2 StringBuilders (String Templating and the joinToString). Also note that there is a isNotEmpty function available on things that have isEmpty

Untitled

[Mike]

@Ellen Spertus I missed something the last time I looked at this. You can see in my example that I append the description string and then append the object rather than using String Templating of Kotlin.

I'm not sure how 'smart' the compiler is, or if it always uses a StringBuilder when there's templating. If it always uses StringBuilder, then your example will be creating a lot of them.

And for above, one could add an operator override for plus that is effectively an append, but I'm not convinced it would help, rather than harm, the readability of the code.