How to import a local library into another local library in sway?

fuel · September 4, 2023, 11:00am

Local Library Imports in Sway: A Challenge

Hello there! We’re grappling with a rather intricate issue concerning local library imports within Sway. Let’s delve into this problem.

The Scenario

Imagine you have a contract consisting of three files: structs.sw, events.sw, and main.sw. I need to import a struct defined in structs.sw into events.sw. It sounds simple, but there’s more to it than meets the eye.

The Contract’s Components

`structs.sw`

This library, structs.sw, holds the struct Counter and its associated default() implementation. The struct Counter is used in the storage of main.sw.

github.com

PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/structs.sw

library;
use std::constants::ZERO_B256;

pub struct Counter {
    value: u64,
    caller: Identity,
    timestamp: u64,
}


impl Counter {
    pub fn default() -> Self {
        Counter {
            value: 0,
            caller: Identity::Address(Address::from(ZERO_B256)),
            timestamp: 0,
        }
     }
}

`events.sw`

Now, events.sw is where the action is. It houses the struct IncrementEvent , which is vital for the indexer, and requires the struct Counter .

github.com

PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/events.sw

library;

use structs::Counter;

pub struct IncrementEvent{
    counter: Counter
}

`main.sw`

In our main file, main.sw, we import both events.sw and structs.sw libraries. But our usage of Counter in the storage is where things get interesting.

github.com

PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/main.sw#L1-L12


      
          contract;
          mod events;
          mod structs;
          use events::*;
          use structs::*;
          
          use std::logging::log;
          use std::auth::msg_sender;
          
          storage {
              counter: Counter = Counter::default(),
          }

Additionally, within the fn increment(), there’s an event named IncrementEvent.

github.com

PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/main.sw#L28-L38


      
          #[storage(read, write)]
          fn increment() {
              let value = storage.counter.value.try_read().unwrap_or(0) + 1;
              let counter = Counter {
                  value: value,
                  caller: msg_sender().unwrap(),
                  timestamp: std::block::timestamp(),
              };
              storage.counter.write(counter);
              log(IncrementEvent {counter});
          }

The Challenge

Here’s where it gets tricky. We need to import struct Counter, which is defined in the structs.sw library, into the events.sw library. But when we run forc build, it throws this error:

>>> forc build
 Compiling library core (/Users/alexey/.forc/git/checkouts/std-9be0d6062747ea7/04a597093e7441898933dd412b8e4dc6ac860cd3/sway-lib-core)
 Compiling library std (git+https://github.com/fuellabs/sway?tag=v0.44.1#04a597093e7441898933dd412b8e4dc6ac860cd3)
 Compiling contract counter-contract (/Users/alexey/Desktop/fuel-counter-contract/counter-contract)
error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/main.sw:1:5
  |
0 | contract;
1 | mod events;
  |     ^^^^^^ Module "events::structs" could not be found.
2 | mod structs;
3 | use events::*;
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Could not find symbol "Counter" in this scope.
7 | }
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Unknown type name "Counter".
7 | }
  |
____

  Aborting due to 3 errors.
Error: Failed to compile counter-contract

Toolchain

Default host: aarch64-apple-darwin
fuelup home: /Users/alexey/.fuelup

installed toolchains
--------------------
beta-3-aarch64-apple-darwin
beta-4-rc.2-aarch64-apple-darwin
latest-aarch64-apple-darwin (default)
hotfix
my-custom-toolchain

active toolchain
-----------------
latest-aarch64-apple-darwin (default)
  forc : 0.44.1
    - forc-client
      - forc-deploy : 0.44.1
      - forc-run : 0.44.1
    - forc-doc : 0.44.1
    - forc-explore : 0.28.1
    - forc-fmt : 0.44.1
    - forc-index : 0.20.7
    - forc-lsp : 0.44.1
    - forc-tx : 0.44.1
    - forc-wallet : 0.3.0
  fuel-core : 0.20.4
  fuel-core-keygen : Error getting version string
  fuel-indexer : 0.20.7

fuels versions
---------------
forc : 0.45
forc-wallet : 0.45

How to reproduce

fuelup self update     
fuelup install latest            
fuelup default latest

git clone https://github.com/PaulZhemanov/fuel-counter-contract.git
cd fuel-counter-contract.
git checkout library-import-issue
cd counter-contract 
forc build

sandusky · September 5, 2023, 8:32pm

Hi there!!

It seems that you should switch the order of imports:

first mod the structs in main.sw
then mod the events

Let me know if that works

fuel · September 5, 2023, 10:09pm

Hi, thats updated code

contract;
mod structs;
mod events;
use structs::*;
use events::*;

use std::logging::log;
use std::auth::msg_sender;

Forc build result

 forc build                                                                                       (library-import-issue+9) 23:08:21 
 Compiling library core (/Users/alexey/.forc/git/checkouts/std-9be0d6062747ea7/04a597093e7441898933dd412b8e4dc6ac860cd3/sway-lib-core)
 Compiling library std (git+https://github.com/fuellabs/sway?tag=v0.44.1#04a597093e7441898933dd412b8e4dc6ac860cd3)
 Compiling contract counter-contract (/Users/alexey/Desktop/fuel-counter-contract/counter-contract)
error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/main.sw:3:5
  |
1 | 
2 | mod structs;
3 | mod events;
  |     ^^^^^^ Module "events::structs" could not be found.
4 | use structs::*;
5 | use events::*;
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Could not find symbol "Counter" in this scope.
7 | }
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Unknown type name "Counter".
7 | }
  |
____

  Aborting due to 3 errors.
Error: Failed to compile counter-contract

repo GitHub - PaulZhemanov/fuel-counter-contract

fuel · September 5, 2023, 10:10pm

Also, I tryed to mod structs in events like here

library;
mod structs;
use structs::Counter;

pub struct IncrementEvent{
    counter: Counter
}

Error:

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:1:5
  |
0 | library;
1 | mod structs;
  |     ^^^^^^^ The file /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events/structs.sw could not be read: No such file or directory (os error 2)
2 | use structs::Counter;
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/main.sw:3:5
  |
1 | 
2 | mod structs;
3 | mod events;
  |     ^^^^^^ Module "events::structs" could not be found.
4 | use structs::*;
5 | use events::*;
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Could not find symbol "Counter" in this scope.
7 | }
  |
____

error
 --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14
  |
4 | 
5 | pub struct IncrementEvent{
6 |     counter: Counter
  |              ^^^^^^^ Unknown type name "Counter".
7 | }
  |
____

  Aborting due to 4 errors.
Error: Failed to compile counter-contract

sandusky · September 6, 2023, 12:46am

I’ve escalated the issue but this seems like you reached one boundary of sway. You can get more details here.

I suggest just to duplicate the properties of counter inside the log . It’s not that elegant but seems to work.

events.sw

library;

pub struct IncrementEvent{
    value: u64,
    caller: Identity,
    timestamp: u64,
}

fuel · September 6, 2023, 7:01am

github.com/FuelLabs/sway

How to import a local library into another local library in sway?

opened 07:00AM - 06 Sep 23 UTC

closed 09:20AM - 07 Sep 23 UTC

chlenc

# Local Library Imports in Sway: A Challenge Hello there! We're grappling wit…h a rather intricate issue concerning local library imports within Sway. Let's delve into this problem. ## The Scenario Imagine you have a contract consisting of three files: `structs.sw`, `events.sw`, and `main.sw`. I need to import a struct defined in `structs.sw` into `events.sw`. It sounds simple, but there's more to it than meets the eye. ### The Contract's Components #### `structs.sw` This library, `structs.sw`, holds the `struct Counter` and its associated `default()` implementation. The `struct Counter` is used in the storage of `main.sw`. https://github.com/PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/structs.sw #### `events.sw` Now, `events.sw` is where the action is. It houses the `struct IncrementEvent` , which is vital for the indexer, and requires the `struct Counter` . https://github.com/PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/events.sw #### `main.sw` In our main file, `main.sw`, we import both `events.sw` and `structs.sw` libraries. But our usage of `Counter` in the storage is where things get interesting. https://github.com/PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/main.sw#L1-L12 Additionally, within the `fn increment()`, there's an event named `IncrementEvent`. https://github.com/PaulZhemanov/fuel-counter-contract/blob/library-import-issue/counter-contract/src/main.sw#L28-L38 ## The Challenge Here's where it gets tricky. We need to import `struct Counter`, which is defined in the `structs.sw` library, into the `events.sw` library. But when we run `forc build`, it throws this error: ``` >>> forc build Compiling library core (/Users/alexey/.forc/git/checkouts/std-9be0d6062747ea7/04a597093e7441898933dd412b8e4dc6ac860cd3/sway-lib-core) Compiling library std (git+https://github.com/fuellabs/sway?tag=v0.44.1#04a597093e7441898933dd412b8e4dc6ac860cd3) Compiling contract counter-contract (/Users/alexey/Desktop/fuel-counter-contract/counter-contract) error --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/main.sw:1:5 | 0 | contract; 1 | mod events; | ^^^^^^ Module "events::structs" could not be found. 2 | mod structs; 3 | use events::*; | ____ error --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14 | 4 | 5 | pub struct IncrementEvent{ 6 | counter: Counter | ^^^^^^^ Could not find symbol "Counter" in this scope. 7 | } | ____ error --> /Users/alexey/Desktop/fuel-counter-contract/counter-contract/src/events.sw:6:14 | 4 | 5 | pub struct IncrementEvent{ 6 | counter: Counter | ^^^^^^^ Unknown type name "Counter". 7 | } | ____ Aborting due to 3 errors. Error: Failed to compile counter-contract ``` ## Toolchain ``` Default host: aarch64-apple-darwin fuelup home: /Users/alexey/.fuelup installed toolchains -------------------- beta-3-aarch64-apple-darwin beta-4-rc.2-aarch64-apple-darwin latest-aarch64-apple-darwin (default) hotfix my-custom-toolchain active toolchain ----------------- latest-aarch64-apple-darwin (default) forc : 0.44.1 - forc-client - forc-deploy : 0.44.1 - forc-run : 0.44.1 - forc-doc : 0.44.1 - forc-explore : 0.28.1 - forc-fmt : 0.44.1 - forc-index : 0.20.7 - forc-lsp : 0.44.1 - forc-tx : 0.44.1 - forc-wallet : 0.3.0 fuel-core : 0.20.4 fuel-core-keygen : Error getting version string fuel-indexer : 0.20.7 fuels versions --------------- forc : 0.45 forc-wallet : 0.45 ``` ### How to reproduce ``` fuelup self update fuelup install latest fuelup default latest git clone https://github.com/PaulZhemanov/fuel-counter-contract.git cd fuel-counter-contract. git checkout library-import-issue cd counter-contract forc build ```

The solution is to change use structs::Counter; to use ::structs::Counter; in events.sw.

system · September 27, 2023, 3:01am

This topic was automatically closed 20 days after the last reply. New replies are no longer allowed.

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How to import a local library into another local library in sway?

Local Library Imports in Sway: A Challenge

The Scenario

The Contract’s Components

structs.sw

events.sw

main.sw

The Challenge

Toolchain

How to reproduce

Related Topics

`structs.sw`

`events.sw`

`main.sw`