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digitalmars.dip.ideas - __HERE__

reply monkyyy <crazymonkyyy gmail.com> writes:
most user written aliasSeq's are repetitive, yet simply nessery 
for metaprograming

```d
alias foo=...;
alias bar=...;
alias fizz=...;
alias foobar=__HERE__;//seq!(foo,bar,fizz)
alias bar=...;
```

`__HERE__` is a special token that evaluates to an alias seq of 
local symbols defined above it

---

```d

auto func1(){...}
auto func2(){...}
auto func3(){...}

static foreach(f;__HERE__){//contains func1, 2 and 3; not f
```

---

like other special tokens it evaluate to the call site

```d
template foo(alias bar=__HERE__){
   alias foo=__HERE__;
}
struct foobar{
   int i;
   float f;
   alias fizz=foo!();//i,f
   bool b;
}
```
Jun 17 2024
next sibling parent Paul Backus <snarwin gmail.com> writes:
On Monday, 17 June 2024 at 16:24:14 UTC, monkyyy wrote:

 most user written aliasSeq's are repetitive, yet simply nessery 
 for metaprograming

 ```d
 alias foo=...;
 alias bar=...;
 alias fizz=...;
 alias foobar=__HERE__;//seq!(foo,bar,fizz)
 alias bar=...;
 ```

 `__HERE__` is a special token that evaluates to an alias seq of 
 local symbols defined above it


Point of comparison: in Python, this is a built-in function 
called `locals()`.

https://docs.python.org/3/library/functions.html#locals
Jun 18 2024
prev sibling parent monkyyy <crazymonkyyy gmail.com> writes:
On Monday, 17 June 2024 at 16:24:14 UTC, monkyyy wrote:

 most user written aliasSeq's are repetitive, yet simply nessery 
 for metaprograming

 ```d
 alias foo=...;
 alias bar=...;
 alias fizz=...;
 alias foobar=__HERE__;//seq!(foo,bar,fizz)
 alias bar=...;
 ```

 `__HERE__` is a special token that evaluates to an alias seq of 
 local symbols defined above it

 ---

 ```d

 auto func1(){...}
 auto func2(){...}
 auto func3(){...}

 static foreach(f;__HERE__){//contains func1, 2 and 3; not f
 ```

 ---

 like other special tokens it evaluate to the call site

 ```d
 template foo(alias bar=__HERE__){
   alias foo=__HERE__;
 }
 struct foobar{
   int i;
   float f;
   alias fizz=foo!();//i,f
   bool b;
 }
 ```


https://gist.github.com/crazymonkyyy/639c5284045c65c74457fdc0d182c3c4

found this pattern today, I suggest someone gets in into 
std.traits,
special tokens have allot of magic, but this works today.
May 30