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Implicit parameters in Python

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# Implicits
Global state can be hard to reason about, but piping dependencies from function to function is a pain. With implicits, you _explicitly_ which function parameters are _implicit_ dependencies. When you call the function, no need to explicilty provide these parameters; instead, the parameters will be implicitly passed! All that's required is that there exists local variables in scope that match the names of the parameters you're calling.
```python3
@implicits("current_user")
def create_task(title, *, current_user):
print(f"{current_user} created a task titled '{title}'")

current_user = "Jaden"
create_task("Hooray, a task!") # Jaden created a task titled 'Hooray, a task!'
create_task("Buy some trackpants") # Jaden created a task titled 'Buy some trackpants'
```

## Usage
1) Install via `pip install implicits`.
2) Import with `from implicits import implicits`.
3) Decorate using `@implicits("names", "of", "implicit", "parameters")`.

## Example
```python3
import logging
import boto3

from implicits import implicits

class Giraffe:
@implicits("logger")
def __init__(self, name, *, logger):
self.name = name
logger.info(f"Creating a Giraffe named {name}")

@property
@implicits("logger")
def full_name(self, *, logger):
logger.info(f"Getting {self.name}'s full name")
return f"{self.name} the Giraffe"

@property
@implicits("food")
def is_hungry(self, *, food):
return "leaves" in food

@implicits("logger")
def main(*, logger):
jeff = Giraffe("Jeff") # Creating a Giraffe named Jeff
name = jeff.full_name # Getting Jeff's full name
food = ["rocks", "dirt"]
logger.info(jeff.is_hungry) # False
food.append("leaves")
logger.info(jeff.is_hungry) # True

logger = logging.getLogger()
logger.setLevel(logging.INFO)
logger.addHandler(logging.StreamHandler())

main()
```

## References

I didn't invent this idea! Quite a few other languages support implicit parameters. The most mainstream of these languages is Scala. [Check out how implicits work in Scala!](https://docs.scala-lang.org/tour/implicit-parameters.html)


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