Support typed bool, int and float in shortcode params

This means that you now can do:

    {{< vidur 9KvBeKu false true 32 3.14 >}}

And the boolean and numeric values will be converted to `bool`, `int` and `float64`.

If you want these to be  strings, they must be quoted:

    {{< vidur 9KvBeKu "false" "true" "32" "3.14" >}}

Fixes #6371

parser/pageparser/item.go

@@ -16,12 +16,15 @@ package pageparser
 import (
 	"bytes"
 	"fmt"
+	"regexp"
+	"strconv"
 )
 
 type Item struct {
-	Type ItemType
-	Pos  int
-	Val  []byte
+	Type     ItemType
+	Pos      int
+	Val      []byte
+	isString bool
 }
 
 type Items []Item
@@ -30,6 +33,36 @@ func (i Item) ValStr() string {
 	return string(i.Val)
 }
 
+func (i Item) ValTyped() interface{} {
+	str := i.ValStr()
+	if i.isString {
+		// A quoted value that is a string even if it looks like a number etc.
+		return str
+	}
+
+	if boolRe.MatchString(str) {
+		return str == "true"
+	}
+
+	if intRe.MatchString(str) {
+		num, err := strconv.Atoi(str)
+		if err != nil {
+			return str
+		}
+		return num
+	}
+
+	if floatRe.MatchString(str) {
+		num, err := strconv.ParseFloat(str, 64)
+		if err != nil {
+			return str
+		}
+		return num
+	}
+
+	return str
+}
+
 func (i Item) IsText() bool {
 	return i.Type == tText
 }
@@ -132,3 +165,9 @@ const (
 	// preserved for later - keywords come after this
 	tKeywordMarker
 )
+
+var (
+	boolRe  = regexp.MustCompile(`^(true$)|(false$)`)
+	intRe   = regexp.MustCompile(`^[-+]?\d+$`)
+	floatRe = regexp.MustCompile(`^[-+]?\d*\.\d+$`)
+)