diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 59b7cafcda..7877b3e119 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -623,7 +623,7 @@ pub fn (mut c Checker) infix_expr(mut node ast.InfixExpr) ast.Type {
 					node.left_type = map_info.key_type
 				}
 				else {
-					c.error('`$node.op.str()` can only be used with an array/map/string',
+					c.error('`$node.op.str()` can only be used with arrays and maps',
 						node.pos)
 				}
 			}
diff --git a/vlib/v/checker/tests/in_mismatch_type.out b/vlib/v/checker/tests/in_mismatch_type.out
index 1a3b16c491..5a9c0a3bb9 100644
--- a/vlib/v/checker/tests/in_mismatch_type.out
+++ b/vlib/v/checker/tests/in_mismatch_type.out
@@ -12,21 +12,21 @@ vlib/v/checker/tests/in_mismatch_type.vv:13:5: error: left operand to `in` does
       |        ~~~~~~
    14 |         println('yeah')
    15 |     }
-vlib/v/checker/tests/in_mismatch_type.vv:16:7: error: `in` can only be used with an array/map/string
+vlib/v/checker/tests/in_mismatch_type.vv:16:7: error: `in` can only be used with arrays and maps
    14 |         println('yeah')
    15 |     }
    16 |     if 3 in s {
       |          ~~
    17 |         println('dope')
    18 |     }
-vlib/v/checker/tests/in_mismatch_type.vv:19:9: error: `in` can only be used with an array/map/string
+vlib/v/checker/tests/in_mismatch_type.vv:19:9: error: `in` can only be used with arrays and maps
    17 |         println('dope')
    18 |     }
    19 |     if `a` in s {
       |            ~~
    20 |         println("oh no :'(")
    21 |     }
-vlib/v/checker/tests/in_mismatch_type.vv:22:7: error: `in` can only be used with an array/map/string
+vlib/v/checker/tests/in_mismatch_type.vv:22:7: error: `in` can only be used with arrays and maps
    20 |         println("oh no :'(")
    21 |     }
    22 |     if 1 in 12 {
@@ -70,8 +70,8 @@ vlib/v/checker/tests/in_mismatch_type.vv:37:5: error: left operand to `!in` does
    39 |     }
 vlib/v/checker/tests/in_mismatch_type.vv:41:5: error: left operand to `!in` does not match the map key type: expected `string`, not `int literal`
    39 |     }
-   40 |
+   40 | 
    41 |     if 5 !in m {
       |        ~~~~~~~
    42 |         println('yay')
-   43 |     }
\ No newline at end of file
+   43 |     }