"if" vs. "takeIf" in Kotlin? -


which of following 2 implementations better:

1.use "if"

fun f1(a: a?): r? {     if (a != null) {         val b = getb(a)         if (b != null && b.f()) {             val c = getc(b)             if (c != null && c.f()) {                 return c.f2()             }         }     }     return null }

2.use "takeif" , "let"

fun f2(a: a?): r? =         ?.let { getb(it) }         ?.takeif { it.f() }         ?.let { getc(it) }         ?.takeif { it.f() }         ?.let { it.f2() }

"takeif" , "let" better approach. though bit harder @ first experienced lambda expression find them full.

kotlin new language , 1 of advantage remove boilerplate code.

fun f2(a: a?): r? =         ?.let { getb(it) }         ?.takeif { it.f() }         ?.let { getc(it) }         ?.takeif { it.f() }         ?.let { it.f2() }

this code snippet that. removed ugly 4 level nesting of if conditions.

hope helps.


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