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Cargo / Activate Features

Activate Features

Enables specified features for a Cargo project at runtime.

Terminal

cargo r -F "<feature1 feature2 ...>"

cargo r -F "<feature1 feature2 ...>"

#!/bin/bash

# Activate Features
cargo {{[r|run]}} {{[-F|--features]}} "{{feature1 feature2 ...}}"

import subprocess

# Activate Features
# Make sure to replace <placeholders> with actual values
def run_command():
    cmd = [
        "cargo",
        "r",
        "-F",
        "\"<feature1 feature2 ...>\""
    ]
    
    try:
        print(f"Executing: {' '.join(cmd)}")
        subprocess.run(cmd, check=True)
    except subprocess.CalledProcessError as e:
        print(f"Error: {e}")
    except FileNotFoundError:
        print("Error: cargo not found. Please install it first.")

if __name__ == "__main__":
    run_command()

When To Use

When needing to test specific functionalities gated by feature flags during development.

Pro Tip

Utilize `--no-default-features` to deactivate default features while selectively activating others for granular control.

Command Builder

Tune the command before you copy it

Back to syntax

Generated Command

cargo r -F "<feature1 feature2 ...>"

Terminal Output

Expected runtime feedback

Simulated preview

Output

Activating features for my_project...

Features activated:
  feature1
  feature2

Running my_project with activated features...

Anatomy of Output

Understanding the result

Activating features: feature_a feature_b... Features Activation Notice

Confirms activation of specified features.

info: succeeded without errors. Execution Summary

Indicates successful activation and run.

error: unknown feature flags provided Unknown Feature Warning

Indicates that some specified features do not exist.

Power User Variants

Optimized versions

cargo run --features "feature_a feature_b"

Activate multiple features for testing.

cargo run --no-default-features --features "custom_feature"

Exclude default features while activating custom functionality.

cargo run --features "feature_1" --verbose

Run with debugging information for enabled features.

Troubleshooting

Common pitfalls

error: feature `feature_name` does not exist

Solution: Ensure the feature is defined in `Cargo.toml` under `[features]`.

error: invalid combination of features activated

Solution: Review feature dependencies for conflicts.

error: expected at least one feature but found none

Solution: Check that features are provided correctly in the command.

Command Breakdown

What each part is doing

cargo: Base Command; The executable that performs this operation. Here it runs Cargo before the shell applies any redirect operators.
r: r|run; The value supplied for r|run.
-F: F| features; The value supplied for F| features.
<feature1 feature2 ...>: feature1 feature2 ...; The value supplied for feature1 feature2 ....
-F: Command Option; Tool-specific option used by this command invocation.

How To Run

Execution path

Step 1
Run the command: cargo run --features "feature1 feature2"
Step 2
Check the output to verify if features are activated successfully.

Alternative Approaches

Comparable commands in other tools

Alternative build tools tools for the same job.

Gradle / Build Project Gradle gradle build Gradle / List Main Tasks Gradle gradle tasks Jhipster / Generate Full Stack Project Monolithic Or Microservices jhipster Ninja / Build Current Directory Parallel Jobs ninja -j <4> Automake / Generate Makefile In Foreign Mode automake --foreign