new operator 'join'

t_operator_test.go

@@ -37,10 +37,12 @@ func TestOperator(t *testing.T) {
 		/*  24 */ {`[1,2,3] map $_`, newList([]any{int64(1), int64(2), int64(3)}), nil},
 		/*  25 */ {`[1,2,3,4] filter ($_ % 2 == 0)`, newList([]any{int64(2), int64(4)}), nil},
 		/*  26 */ {`max=0; [2,3,1] digest max=(($_ > max) ? {$_} :: {max})`, int64(3), nil},
+		/*  27 */ {`["a","b"] join ["x"]`, newList([]any{"a", "b", "x"}), nil},
+		/*  28 */ {`["a","b"] join ["x"-true]`, nil, `[1:21] left operand 'x' [string] and right operand 'true' [bool] are not compatible with operator "-"`},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")
 
-	// runTestSuiteSpec(t, section, inputs, 25)
+	// runTestSuiteSpec(t, section, inputs, 28)
 	runTestSuite(t, section, inputs)
 }