Can I use the bool attribute with the custom tag? (like "disabled")

[hajimegane]

I noticed that bool attributes cannot work in the custom tag's "opts".

<my-app>
  <button onclick="{toggle}">Click</button>
  <my-tag aaa="{this.flg}" disabled="{this.flg}"></my-tag>

  this.flg = false
  toggle() {this.flg = !this.flg}
</my-app>

<my-tag>
  <div>aaa: {opts.aaa}</div>
  <div>disabled: {opts.disabled}</div>
</my-tag>

1 click: aaa=true, disabled=null
2 click: aaa=null, disabled=disabled
3 click: aaa=true, disabled=disabled

But I expected below.
1 click: aaa=true, disabled=disabled
2 click: aaa=null, disabled=null
3 click: aaa=true, disabled=disabled

Or below.
1 click: aaa=true, disabled=true
2 click: aaa=null, disabled=null
3 click: aaa=true, disabled=true

Should I not use bool attributes with custom tags? (Or Should I use "opts.__disabled"?)
Thanks in advance for your answer.

[aMarCruz]

@hajimegane , this bug was introduced by a change in riot which removes the attributes with falsy values except zero, so you can use a number:

  <my-app>
    <button onclick="{toggle}">Click</button>
    <my-tag aaa="{this.flg}" disabled="{this.flg}"></my-tag>
    this.flg = 0
    toggle() {this.flg ^= 1}
  </my-app>

  <my-tag>
    <div>aaa: {opts.aaa}</div>
    <div>disabled: {opts.__disabled}</div>
  </my-tag>

as you are right, disabled is __disabled, but it is better not to use this name because in future versions may be that this behavior change.

[hajimegane]

@aMarCruz Thank you for your reply. I tried to set a number value into the disabled attribute but the result is not changed, so the value of opts.disabled is null -> "disabled" -> "disabled".

I think that the special bool attributes that start __ may be not necessary because all attributes with a expression, include not start __, remove automatically if the value is a falsy. And, whether the attribute is removed with the value zero should be unified regardless of the bool attributes such as disabled.
Is this my understanding the right?

Here is my validation code: http://plnkr.co/edit/ycy8moa3N4RrHSyrzCXe

[aMarCruz]

@hajimegane it is so. The use of __ in boolean attributes comes from earlier versions of riot that support IE8 and it remains for compatibility with existing code, it is likely to be remove in future versions.

[hajimegane]

@aMarCruz I understand. Thank you.

[GianlucaGuarini]

fixed in riot@3.0.0 http://plnkr.co/edit/OOznRNFpSUtk57gptMxr?p=preview