# Internal compiler error: Unable to determine ID for log instance. Please file an issue on the repository and include the code that triggered this error

**URL:** <https://forum.fuel.network/t/internal-compiler-error-unable-to-determine-id-for-log-instance-please-file-an-issue-on-the-repository-and-include-the-code-that-triggered-this-error/2018>\
**Category:** Sway\
**Created:** [March 13, 2023, 8:10am UTC](https://forum.fuel.network/t/internal-compiler-error-unable-to-determine-id-for-log-instance-please-file-an-issue-on-the-repository-and-include-the-code-that-triggered-this-error/2018 "2023-03-13T08:10:29Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![fuel](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.fuel.network/fuel/32/1677_2.png) [@fuel](https://forum.fuel.network/u/fuel)\
**Post date:** [March 13, 2023, 8:10am UTC](https://forum.fuel.network/t/internal-compiler-error-unable-to-determine-id-for-log-instance-please-file-an-issue-on-the-repository-and-include-the-code-that-triggered-this-error/2018/1 "2023-03-13T08:10:29Z")

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Hi guys!  
I’m trying to get some data from the token contract from the predicate like here

```auto
predicate;
use token_abi::Token;
...
fn main() -> bool {
    let res = abi(Token, ASSET_1).config();
    log(res.decimals);
...

```

and having this error

```auto
^^/p/f/l/predicate >>> forc build (1) (*master+54) 08:04:55 
  Compiled library "core".
  Compiled library "std".
  Compiled library "token_abi".
error
  --> /Users/alexey/.forc/git/checkouts/std-57e47d01450577b4/c32b0759d25c0b515cbf535f9fb9b8e6fda38ff2/sway-lib-std/src/logging.sw:9:5
   |
 7 | 
 8 | pub fn log<T>(value: T) {
 9 | __log::<T>(value);
   | ^^^^^^^^^^^^^^^^^ Internal compiler error: Unable to determine ID for log instance.
Please file an issue on the repository and include the code that triggered this error.
10 | }
   |
____

  Aborting due to 1 error.

```

---

<div class="post-metadata">

**Author:** ![furnic](https://avatars.discourse-cdn.com/v4/letter/f/97f17d/32.png) [@furnic](https://forum.fuel.network/u/furnic)\
**Post date:** [March 13, 2023, 4:54pm UTC](https://forum.fuel.network/t/internal-compiler-error-unable-to-determine-id-for-log-instance-please-file-an-issue-on-the-repository-and-include-the-code-that-triggered-this-error/2018/2 "2023-03-13T16:54:07Z")

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You cannot use `log` in a predicate.  
The easiest way I know to debug this is to temporarily change your predicate to a script and perform any temporary logging there, then change it back after debugging.