Sink and Source are different length Vecs - concatenation

Question

The following code is to concatenate two strings. It is getting compiled but shows errors after elaboration.
Code:
package problems
import chisel3._
import chisel3.util._
class Compare1 extends Module {
val io = IO(new Bundle {
val in1 = Input(Vec(5, UInt(3.W)))
val in2 = Input(Vec(5, UInt(3.W)))
val out = Output(Vec(6, UInt(3.W)))
})
val L = 5
io.out := io.in2
val ml = 4
for (l <- 0 until ml) {
when (io.in2(l) === io.in1(L - ml + l)) {
io.out(l) := io.in1(l)
}
}
val m = (2*L) - ml
for (i <- ml until m) {
io.out(i) := io.in2(i - (L - ml))
}
}
Testbench:
I am poking 19333 and 23599 and expecting 154671
Error:
To sum it up, this is what I get
Errors: 1: in the following tutorials
Tutorial Compare1: exception Connection between sink (Vec(chisel3.core.UInt#80, chisel3.core.UInt#82, chisel3.core.UInt#84, chisel3.core.UInt#86, chisel3.core.UInt#88, chisel3.core.UInt#8a)) and source (Vec(chisel3.core.UInt#6a, chisel3.core.UInt#6c, chisel3.core.UInt#6e, chisel3.core.UInt#70, chisel3.core.UInt#72)) failed #: Sink and Source are different length Vecs.

Answer 1

The error is with the line: io.out := io.in2, io.out is a Vec of length 6 while io.in2 is a Vec of length 5. As the error says, you cannot connect Vecs of different lengths together.
If you wish to connect indices 0 to 4 of io.in2 to io.out, try
for (i <- 0 until io.in2.size) { io.out(i) := io.in2(i) }