How do I use a URL in a macro?

[thor...@gmail.com]

Hello all,

I'm having trouble understanding why a simple macro I wrote doesn't work properly:

```

\define todoLink(url, name:"Link")

<a href="$url$" class="tc-tiddlylink-external" target="_blank" rel="noopener noreferrer">$name$</a>

\end

```

If I use `<<todoLink http://foo.org bar>>` to call my shiny new macro, the first parameter seems to be completely ignored:

`<a href="bar" class="tc-tiddlylink-external" target="_blank" rel="noopener noreferrer">Link</a>`

On the other hand, if I use the `<$macrocall>` syntax, like `<$macrocall $name="todoLink" url="http://foo.org" name="bar"/>`, I get the expected behavior.

<a href="http://foo.org" class="tc-tiddlylink-external" target="_blank" rel="noopener noreferrer">bar</a>

Ultimately, I'll be using this macro in tiddlers with a `url` field, so I _think I'll have to use the `<$macrocall>` syntax. But I feel like this behavior will bite me in the future. Why does first method of calling the macro produce incorrect output, and why does the second work?

I can make the first method work by putting the URL in quotes, but I would like to avoid that in general because it's more typing :): `<<todoLink "http://foo.org" bar>>`. Why are the quotes required? I thought macro expansion substituted text without treating the macro inputs as WikiText?

My browser is Opera 78.0.4093.184 on Windows 10, and my TiddlyWiki version is 5.1.21. Thanks for any help!

[Eric Shulman]

On Monday, September 20, 2021 at 12:35:18 AM UTC-7 thor...@gmail.com wrote:

I can make the first method work by putting the URL in quotes, but I would like to avoid that in general because it's more typing :): `<<todoLink "http://foo.org" bar>>`. Why are the quotes required? I thought macro expansion substituted text without treating the macro inputs as WikiText?

The `<<macroname param param param>>` syntax, in addition to handling *unnamed* parameters, also recognizes *named* parameters, using `name:value`.

Thus, a value like `http://foo.org` is parsed as a parameter named "http", with a value of "//foo.org".  By enclosing it in quotes, it avoids the named parameter parsing and passes it into the macro as a single parameter value

So... you can use the quotes to bypass the parameter name parsing: `<<todoLink "http://foo.org" bar>>`

or, you can add a parameter *name*, like this:  `<<todoLink url:http://foo.org bar>>`.

Either way, it's going to be "more typing" (but only a little).  Still, its less typing than the full `<$macrocall ...>` widget syntax.

-e

[thor...@gmail.com]

Thank you, your explanation it makes it very clear what's going on. Whoops :D!

> Either way, it's going to be "more typing" (but only a little).  Still, its less typing than the full `<$macrocall ...>` widget syntax.

In this case, I will be using the `<$macrocall ...>` syntax because I want to create a template tiddler using `tm-new-tiddler`. This template contains wikitext which field-transcludes a URL field. However, if I want to create a generic macro for links where I might want to specify the URL scheme, I know to watch out for my colons this time :D!