isLowerCase  
  Returns true if this character is lower case.
A character is considered to be a lower case character if its category is CharCategory.LOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
Since Kotlin
1.5Samples
import java.util.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val chars = listOf('a', 'λ', 'A', '1', '+')
val (lowerCases, notLowerCases) = chars.partition { it.isLowerCase() }
println(lowerCases) // [a, λ]
println(notLowerCases) // [A, 1, +] 
   //sampleEnd
}Returns true if this character is lower case.
A character is considered to be a lower case character if its category is CharCategory.LOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
Since Kotlin
1.5Samples
import java.util.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val chars = listOf('a', 'λ', 'A', '1', '+')
val (lowerCases, notLowerCases) = chars.partition { it.isLowerCase() }
println(lowerCases) // [a, λ]
println(notLowerCases) // [A, 1, +] 
   //sampleEnd
}Returns true if this character is lower case.
A character is considered to be a lower case character if its category is CharCategory.LOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
Since Kotlin
1.0Samples
import java.util.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val chars = listOf('a', 'λ', 'A', '1', '+')
val (lowerCases, notLowerCases) = chars.partition { it.isLowerCase() }
println(lowerCases) // [a, λ]
println(notLowerCases) // [A, 1, +] 
   //sampleEnd
}Returns true if this character is lower case.
A character is considered to be a lower case character if its category is CharCategory.LOWERCASE_LETTER, or it has contributory property Other_Lowercase as defined by the Unicode Standard.
Since Kotlin
1.3Samples
import java.util.*
import kotlin.test.*
fun main() { 
   //sampleStart 
   val chars = listOf('a', 'λ', 'A', '1', '+')
val (lowerCases, notLowerCases) = chars.partition { it.isLowerCase() }
println(lowerCases) // [a, λ]
println(notLowerCases) // [A, 1, +] 
   //sampleEnd
}