KT.UNNECESSARY_LET

Unnecessary 'let' expression

let expressions are used extensively in our code for null-checking and chaining functions, but sometimes their usage should be replaced with an ordinary method/extension function call to reduce visual complexity.

Noncompliant Code

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a.let { print(it) } // can be replaced with 'print(a)'
a.let { it.plus(1) } // can be replaced with 'a.plus(1)'
a?.let { it.plus(1) } // can be replaced with 'a?.plus(1)'
a?.let { that -> that.plus(1) }?.let { it.plus(1) } // can be replaced with 'a?.plus(1)?.plus(1)'
a.let { 1.plus(1) } // can be replaced with '1.plus(1)'
a?.let { 1.plus(1) } // can be replaced with 'if (a != null) 1.plus(1)'

Compliant Code

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a?.let { print(it) }
a?.let { 1.plus(it) } ?.let { msg -> print(msg) }
a?.let { it.plus(it) }
val b = a?.let { 1.plus(1) }