why first - not displayed in title element?

[practicemp]

In markdown file:
#### --backup-dir=DIR

hexo server output:

<h4 id="–backup-dir-DIR">
    <a href="#–backup-dir-DIR" class="headerlink" title="–backup-dir=DIR"></a>
    –backup-dir=DIR
</h4>

The first - not displayed in the h4 element id & content, also to href and title of the a element .

Then I try this:
#### \--backup-dir=DIR
hexo server output:

<h4 id="backup-dir-DIR">
    <a href="#backup-dir-DIR" class="headerlink" title="--backup-dir=DIR"></a>
    --backup-dir=DIR
</h4>

The first and second - not displayed in the h4 element id , also to href of the a element .

What should i do ?

[tcrowe]

I did a test with marked.

./test.md (input)

# --one

one

## --two

two

### --three

three

#### --backup-dir=DIR

four

marked test.md > test.html

./test.html (output)

<h1 id="--one">--one</h1>
<p>one</p>
<h2 id="--two">--two</h2>
<p>two</p>
<h3 id="--three">--three</h3>
<p>three</p>
<h4 id="--backup-dirdir">--backup-dir=DIR</h4>
<p>four</p>

This looks okay. So the next step is to look at where we might be touching the output.

---

@practicemp You didn't fill out the issue template so I assumed you are using hexo-renderer-marked. If you are using a different markdown renderer you can let me know. npm ls --depth 0

[practicemp]

@tcrowe
Node version v8.12.0
Hexo and Plugin version

$ npm ls --depth 0
hexo-site@0.0.0 /Users/practicemp/blog
├── hexo@3.8.0
├── hexo-deployer-rsync@0.1.3
├── hexo-generator-archive@0.1.5
├── hexo-generator-category@0.1.3
├── hexo-generator-index@0.2.1
├── hexo-generator-sitemap@1.2.0
├── hexo-generator-tag@0.2.0
├── hexo-renderer-ejs@0.3.1
├── hexo-renderer-jade@0.4.1
├── hexo-renderer-marked@0.3.2
├── hexo-renderer-sass@0.3.2
├── hexo-renderer-stylus@0.3.3
└── hexo-server@0.3.3

The part of the renderer referenced in my theme file (post.pug):

.post-content
    != page.content 

[tcrowe]

@practicemp Thanks. I will take another look tomorrow morning and see where we are changing the headings.

[tcrowe]

Are you using the toc helper, @practicemp? https://hexo.io/docs/helpers#toc

[practicemp]

@tcrowe
Yes:

.toc
    != toc(page.content,{list_number: false})

[curbengh]

it's due to

marked:
  smartypants: true #default

which converts double-dash (--) into en dash (–, or &#2013)

a workaround is to disable the option, but that also stop replacing double quote ("") with (“” ), it's fine if you don't need them.

Related to #89