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|
package markdown
import (
"encoding/json"
"errors"
"fmt"
"html/template"
"strings"
)
var ErrUnkownLexType = errors.New("unkown lex type")
type block interface {
Eval() (template.HTML, *ParseError)
}
type tree struct {
blocks []block
}
func (t *tree) Eval() (template.HTML, *ParseError) {
var content template.HTML
for _, c := range t.blocks {
ct, err := c.Eval()
if err != nil {
return "", err
}
content += ct
}
return content, nil
}
func (t *tree) String() string {
b, _ := json.MarshalIndent(t, "", " ")
return string(b)
}
func ast(lxs *lexers) (*tree, *ParseError) {
tr := new(tree)
newLine := true
for lxs.Next() {
b, err := getBlock(lxs, newLine)
if err != nil {
return nil, err
}
if b != nil {
tr.blocks = append(tr.blocks, b)
}
if !lxs.Finished() {
newLine = lxs.Current().Type == lexerBreak
}
}
return tr, nil
}
func getBlock(lxs *lexers, newLine bool) (block, *ParseError) {
var b block
var err *ParseError
switch lxs.Current().Type {
case lexerHeader:
if !newLine {
b, err = paragraph(lxs, false)
} else {
b, err = header(lxs)
}
case lexerExternal:
if newLine && lxs.Current().Value == "