Qute: tag parameter validation

[FroMage]

Description

ATM we can declare tag parameters like this:

{@java.lang.Boolean img}
{@java.lang.Integer size}
{@fr.epardaud.model.User it}

<!-- FIXME: there appears to be a size value coming from outer space -->
<span class="user-link" title="{it.userName} currently has {it.reputation} reputation points">
<a href="{uri:Users.view(it.userName)}">
{#if img??}
{it.reputation}
{/if}
{#if img??}
{#gravatar it.email size=size.or(20) default='mm' /}
{/if}
{it.userName}</a></span>

But we have the following issues:

• I tried using {@boolean img} and got an error. I guess the wrapper type works fine as a workaround, but perhaps we could relax this and make it an alias?
• Call-sites are not validated: we don't verify that we call this tag with {user userValue img=booleanValue/}
• Default values are not supported: I can't call this with {user userValue/} without using img?? in the tag, and if we do call-site validation this might be disallowed because one parameter will be missing. So perhaps we need to allow default parameter values:

{@java.lang.Boolean img=false}
{@java.lang.Integer size=20}
{@fr.epardaud.model.User it}

<!-- FIXME: there appears to be a size value coming from outer space -->
<span class="user-link" title="{it.userName} currently has {it.reputation} reputation points">
<a href="{uri:Users.view(it.userName)}">
{#if img}
{it.reputation}
{/if}
{#if img}
{#gravatar it.email size=size default='mm' /}
{/if}
{it.userName}</a></span>

Implementation ideas

No response

[quarkus-bot]

/cc @mkouba

[gbourant]

I'm making a Qute component library, the tag section would fit perfect if it had validation like a normal template does.

[mkouba]

I'm making a Qute component library, the tag section would fit perfect if it had validation like a normal template does.

Do you mean the call site validation?

[mkouba]

• I tried using {@boolean img} and got an error. I guess the wrapper type works fine as a workaround, but perhaps we could relax this and make it an alias?

I believe that this was fixed long time ago, i.e. you can use {@boolean img}.

• Call-sites are not validated: we don't verify that we call this tag with {user userValue img=booleanValue/}

Yes, this one is a little bit more complicated because we don't have a way to validate sections in a template yet. It's on my TODO though ;-).

• Default values are not supported: I can't call this with {user userValue/} without using img?? in the tag, and if we do call-site validation this might be disallowed because one parameter will be missing. So perhaps we need to allow default parameter values:

This should be supported, i.e. you should be able to use {@boolean img=false}.

[gbourant]

I'm making a Qute component library, the tag section would fit perfect if it had validation like a normal template does.

Do you mean the call site validation?

Yes! :)