for <condition> {} loop does not work in templates $tmpl()

[gechandesu]

V version: V 0.4.9 d2b30df, press to see full `v doctor` output

V full version	V 0.4.9 5ec9bb5.d2b30df
OS	linux, Linux version 6.6.8-arch1-1 (linux@archlinux) (gcc (GCC) 13.2.1 20230801, GNU ld (GNU Binutils) 2.41.0) #1 SMP PREEMPT_DYNAMIC Thu, 21 Dec 2023 19:01:01 +0000
Processor	16 cpus, 64bit, little endian, 12th Gen Intel(R) Core(TM) i5-1240P
Memory	5.23GB/15.35GB
V executable	/home/ge/.vlang/v
V last modified time	2025-01-12 11:38:38
V home dir	OK, value: /home/ge/.vlang
VMODULES	OK, value: /home/ge/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/ge/Code/experiments/v_templating
Git version	git version 2.47.1
V git status	weekly.2024.53-79-gd2b30df1
.git/config present	true
cc version	cc (GCC) 14.2.1 20240910
gcc version	gcc (GCC) 14.2.1 20240910
clang version	clang version 18.1.8
tcc version	tcc version 0.9.28rc 2024-07-31 HEAD@1cee0908 (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 0134e9b9
emcc version	N/A
glibc version	ldd (GNU libc) 2.40

What did you do?
./v -g -o vdbg cmd/v && ./vdbg main.v && main

module main

struct User {
    name string
    age int
}

fn main() {
    mut users := []User{}
    users << User{name: 'John Doe', age: 27}
    users << User{name: 'Jane Doe', age: 16}
    page := $tmpl('users.tmpl')
    println(page)
}

users.tmpl:

@for user in users {
    @{user.name} is @{user.age} years old
}

What did you see?

users.tmpl:20:1: error: unexpected eof, expecting `}`

What did you expect to see?

Generated text with users list:

John Doe is 27 years old
Jane Doe is 16 years old

According to the documentation it should work.

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[huly-for-github]

Connected to Huly®: V_0.6-21877

[islonely]

For variables you don't need the curly braces; just @user.name

[gechandesu]

For variables you don't need the curly braces; just @user.name

The error is reproduced despite the presence of curly braces. In addition, curly braces solve the parsing problem when the data in the template follows the variable name without spaces (e.g. dot at the end of a sentence).

[jorgeluismireles]

I have used @for … @end instead using {}

[gechandesu]

I have used @for … @end instead using {}

Oh, it worked with:

@for user in users
    @user.name is @user.age years old
@end

V templating is so inconsistent...

How about deprecate @for <condition> {} syntax?

Also both $ and @ signs can be used for variables. It would probably be nice to have one way here too.

[jorgeluismireles]

I think V borrowed the template syntax of @ from other frameworks to permit have javascript valid identifiers $, {, } untouched in the template. So for example (code not tested):

<script>
function discount(a) { alert('$' + 0.10*a); }
</script>
<table>
<tr><td>User</td><td>Discount</td></tr>
@for user in users
 <tr>
 <td>@user.name</td>
 <td><button onclick = "discount(@user.payment)">$ Discount</td>
</tr>
@end
</table>

[medvednikov]

Also both $ and @ signs can be used for variables. It would probably be nice to have one way here too.

I agree. I tried doing that, but it's pretty tricky. The templates need to be re-written with a real parser.