Fix printf formatting

diff --git a/doc_test.go b/doc_test.go
index 7c0e677..6945241 100644
--- a/doc_test.go
+++ b/doc_test.go

@@ -69,13 +69,13 @@
 		fmt.Println("User is ", user, ". Password is ", password)
 
 		// show where elements are in the file
-		fmt.Println("User position: %v", configTree.GetPosition("user"))
-		fmt.Println("Password position: %v", configTree.GetPosition("password"))
+		fmt.Printf("User position: %v\n", configTree.GetPosition("user"))
+		fmt.Printf("Password position: %v\n", configTree.GetPosition("password"))
 
 		// use a query to gather elements without walking the tree
 		results, _ := config.Query("$..[user,password]")
 		for ii, item := range results.Values() {
-			fmt.Println("Query result %d: %v", ii, item)
+			fmt.Printf("Query result %d: %v\n", ii, item)
 		}
 	}
 }

diff --git a/match.go b/match.go
index 423a869..085d294 100644
--- a/match.go
+++ b/match.go

@@ -202,7 +202,7 @@
 	fn, ok := (*ctx.filters)[f.Name]
 	if !ok {
 		panic(fmt.Sprintf("%s: query context does not have filter '%s'",
-			f.Pos, f.Name))
+			f.Pos.String(), f.Name))
 	}
 	switch castNode := tomlValueCheck(node, ctx).(type) {
 	case *TomlTree:

diff --git a/position.go b/position.go
index 1f26245..0ac907c 100644
--- a/position.go
+++ b/position.go

@@ -6,13 +6,11 @@
 	"fmt"
 )
 
-/*
-  Position of a document element within a TOML document.
-
-  Line and Col are both 1-indexed positions for the element's line number and
-  column number, respectively.  Values of zero or less will cause Invalid(),
-  to return true.
-*/
+// Position of a document element within a TOML document.
+//
+// Line and Col are both 1-indexed positions for the element's line number and
+// column number, respectively.  Values of zero or less will cause Invalid(),
+// to return true.
 type Position struct {
 	Line int // line within the document
 	Col  int // column within the line
@@ -24,7 +22,7 @@
 	return fmt.Sprintf("(%d, %d)", p.Line, p.Col)
 }
 
-// Returns whether or not the position is valid (i.e. with negative or
+// Invalid returns whether or not the position is valid (i.e. with negative or
 // null values)
 func (p *Position) Invalid() bool {
 	return p.Line <= 0 || p.Col <= 0

diff --git a/queryparser.go b/queryparser.go
index 8c0de8d..e7caa1e 100644
--- a/queryparser.go
+++ b/queryparser.go

@@ -138,7 +138,6 @@
 		return nil // allow EOF at this stage
 	}
 	return p.parseError(tok, "expected match expression")
-	return nil
 }
 
 func (p *queryParser) parseBracketExpr() queryParserStateFn {

diff --git a/toml_test.go b/toml_test.go
index c89b973..e7f8f16 100644
--- a/toml_test.go
+++ b/toml_test.go

@@ -65,7 +65,7 @@
 	}
 
 	if tt, ok := values[0].(*TomlTree); !ok {
-		t.Errorf("Expected type of TomlTree: %T Tv", values[0], values[0])
+		t.Errorf("Expected type of TomlTree: %T", values[0])
 	} else if tt.Get("a") != int64(1) {
 		t.Errorf("Expected 'a' with a value 1: %v", tt.Get("a"))
 	} else if tt.Get("b") != int64(2) {