chore: initial commit

.editorconfig

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+root = true
+
+[*]
+indent_style = tab
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.yml]
+indent_style = space
+
+[*.md]
+trim_trailing_whitespace = false

.gitattributes

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+* text=auto eol=lf

.gitignore

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+*.log*
+.DS_Store
+.idea/
+node_modules/

.prettierrc.json

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+{
+	"useTabs": true,
+	"trailingComma": "all",
+	"overrides": [
+		{
+			"files": "*.md",
+			"options": {
+				"useTabs": false,
+				"trailingComma": "none"
+			}
+		}
+	]
+}

.vscode/extensions.json

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+{
+	"recommendations": ["EditorConfig.EditorConfig", "esbenp.prettier-vscode"]
+}

.vscode/settings.json

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+{
+	"editor.defaultFormatter": "esbenp.prettier-vscode",
+	"editor.formatOnSave": true
+}

CHANGELOG.md

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+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.0.0] - 2020-12-27
+
+### Added
+
+- `PolymorphicPropsWithoutRef` and `PolymorphicPropsWithRef` types for appending `as` to component props
+- `PolymorphicForwardRefExoticComponent`, `PolymorphicMemoExoticComponent` and `PolymorphicLazyExoticComponent` types to support exotic components
+
+[unreleased]: https://github.com/kripod/react-polymorphic-types/compare/v1.0.0...HEAD
+[1.0.0]: https://github.com/kripod/react-polymorphic-types/releases/tag/v1.0.0

CODE_OF_CONDUCT.md

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+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+We as members, contributors, and leaders pledge to make participation in our
+community a harassment-free experience for everyone, regardless of age, body
+size, visible or invisible disability, ethnicity, sex characteristics, gender
+identity and expression, level of experience, education, socio-economic status,
+nationality, personal appearance, race, religion, or sexual identity
+and orientation.
+
+We pledge to act and interact in ways that contribute to an open, welcoming,
+diverse, inclusive, and healthy community.
+
+## Our Standards
+
+Examples of behavior that contributes to a positive environment for our
+community include:
+
+- Demonstrating empathy and kindness toward other people
+- Being respectful of differing opinions, viewpoints, and experiences
+- Giving and gracefully accepting constructive feedback
+- Accepting responsibility and apologizing to those affected by our mistakes,
+  and learning from the experience
+- Focusing on what is best not just for us as individuals, but for the
+  overall community
+
+Examples of unacceptable behavior include:
+
+- The use of sexualized language or imagery, and sexual attention or
+  advances of any kind
+- Trolling, insulting or derogatory comments, and personal or political attacks
+- Public or private harassment
+- Publishing others' private information, such as a physical or email
+  address, without their explicit permission
+- Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Enforcement Responsibilities
+
+Community leaders are responsible for clarifying and enforcing our standards of
+acceptable behavior and will take appropriate and fair corrective action in
+response to any behavior that they deem inappropriate, threatening, offensive,
+or harmful.
+
+Community leaders have the right and responsibility to remove, edit, or reject
+comments, commits, code, wiki edits, issues, and other contributions that are
+not aligned to this Code of Conduct, and will communicate reasons for moderation
+decisions when appropriate.
+
+## Scope
+
+This Code of Conduct applies within all community spaces, and also applies when
+an individual is officially representing the community in public spaces.
+Examples of representing our community include using an official e-mail address,
+posting via an official social media account, or acting as an appointed
+representative at an online or offline event.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported to the community leaders responsible for enforcement at
+[email protected].
+All complaints will be reviewed and investigated promptly and fairly.
+
+All community leaders are obligated to respect the privacy and security of the
+reporter of any incident.
+
+## Enforcement Guidelines
+
+Community leaders will follow these Community Impact Guidelines in determining
+the consequences for any action they deem in violation of this Code of Conduct:
+
+### 1. Correction
+
+**Community Impact**: Use of inappropriate language or other behavior deemed
+unprofessional or unwelcome in the community.
+
+**Consequence**: A private, written warning from community leaders, providing
+clarity around the nature of the violation and an explanation of why the
+behavior was inappropriate. A public apology may be requested.
+
+### 2. Warning
+
+**Community Impact**: A violation through a single incident or series
+of actions.
+
+**Consequence**: A warning with consequences for continued behavior. No
+interaction with the people involved, including unsolicited interaction with
+those enforcing the Code of Conduct, for a specified period of time. This
+includes avoiding interactions in community spaces as well as external channels
+like social media. Violating these terms may lead to a temporary or
+permanent ban.
+
+### 3. Temporary Ban
+
+**Community Impact**: A serious violation of community standards, including
+sustained inappropriate behavior.
+
+**Consequence**: A temporary ban from any sort of interaction or public
+communication with the community for a specified period of time. No public or
+private interaction with the people involved, including unsolicited interaction
+with those enforcing the Code of Conduct, is allowed during this period.
+Violating these terms may lead to a permanent ban.
+
+### 4. Permanent Ban
+
+**Community Impact**: Demonstrating a pattern of violation of community
+standards, including sustained inappropriate behavior, harassment of an
+individual, or aggression toward or disparagement of classes of individuals.
+
+**Consequence**: A permanent ban from any sort of public interaction within
+the community.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 2.0, available at
+[https://www.contributor-covenant.org/version/2/0/code_of_conduct.html][v2.0].
+
+Community Impact Guidelines were inspired by
+[Mozilla's code of conduct enforcement ladder][mozilla coc].
+
+For answers to common questions about this code of conduct, see the FAQ at
+[https://www.contributor-covenant.org/faq][faq]. Translations are available
+at [https://www.contributor-covenant.org/translations][translations].
+
+[homepage]: https://www.contributor-covenant.org
+[v2.0]: https://www.contributor-covenant.org/version/2/0/code_of_conduct.html
+[mozilla coc]: https://github.com/mozilla/diversity
+[faq]: https://www.contributor-covenant.org/faq
+[translations]: https://www.contributor-covenant.org/translations

LICENSE

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+The MIT License (MIT)
+
+Copyright (c) 2020 Kristóf Poduszló
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# react-polymorphic-types
+
+Zero-runtime polymorphic component definitions for React
+
+[![npm](https://img.shields.io/npm/v/react-polymorphic-types)](https://www.npmjs.com/package/react-polymorphic-types)
+[![npm bundle size](https://img.shields.io/bundlephobia/min/react-polymorphic-types)](https://bundlephobia.com/result?p=react-polymorphic-types)
+
+## Motivation
+
+Being a successor to [react-polymorphic-box](https://github.com/kripod/react-polymorphic-box), this project offers more accurate typings with less overhead.
+
+## Features
+
+- Automatic code completion, based on the value of the `as` prop
+- Static type checking against the associated component’s inferred props
+- HTML element name validation
+
+## Usage
+
+A `Heading` component can demonstrate the effectiveness of polymorphism:
+
+```tsx
+<Heading color="rebeccapurple">Heading</Heading>
+<Heading as="h3">Subheading</Heading>
+```
+
+Custom components like the previous one may utilize the package as shown below.
+
+```tsx
+import type { PolymorphicPropsWithoutRef } from "react-polymorphic-types";
+
+// An HTML tag or a different React component can be rendered by default
+export const HeadingDefaultElement = "h2";
+
+// Component-specific props should be specified separately
+export type HeadingOwnProps = {
+  color?: string;
+};
+
+// Extend own props with others inherited from the underlying element type
+// Own props take precedence over the inherited ones
+export type HeadingProps<
+  T extends React.ElementType = typeof HeadingDefaultElement
+> = PolymorphicPropsWithoutRef<HeadingOwnProps, T>;
+
+export function Heading<
+  T extends React.ElementType = typeof HeadingDefaultElement
+>({ as, color, style, ...restProps }: HeadingProps<T>) {
+  const Element: React.ElementType = as || ButtonDefaultElement;
+  return <Element style={{ color, ...style }} {...restProps} />;
+}
+```
+
+### With [`React.forwardRef`](https://reactjs.org/docs/react-api.html#reactforwardref)
+
+```tsx
+import * as React from "react";
+import type { PolymorphicForwardRefExoticComponent } from "react-polymorphic-types";
+import { Heading, HeadingDefaultElement, HeadingOwnProps } from "./Heading";
+
+export const RefForwardingHeading: PolymorphicForwardRefExoticComponent<
+  HeadingOwnProps,
+  HeadingDefaultElement
+> = React.forwardRef(Heading);
+```
+
+### With [`React.memo`](https://reactjs.org/docs/react-api.html#reactmemo)
+
+```tsx
+import * as React from "react";
+import type { PolymorphicMemoExoticComponent } from "react-polymorphic-types";
+import { Heading, HeadingDefaultElement, HeadingOwnProps } from "./Heading";
+
+export const MemoizedHeading: PolymorphicMemoExoticComponent<
+  HeadingOwnProps,
+  HeadingDefaultElement
+> = React.memo(Heading);
+```
+
+### With [`React.lazy`](https://reactjs.org/docs/react-api.html#reactlazy)
+
+```tsx
+import * as React from "react";
+import type { PolymorphicLazyExoticComponent } from "react-polymorphic-types";
+import type { HeadingDefaultElement, HeadingOwnProps } from "./Heading";
+
+export const LazyHeading: PolymorphicLazyExoticComponent<
+  HeadingOwnProps,
+  HeadingDefaultElement
+> = React.lazy(async () => {
+  const { Heading } = await import("./Heading");
+  return { default: Heading };
+});
+```

index.d.ts

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+type Merge<T, U> = Omit<T, keyof U> & U;
+
+type PropsWithAs<P, T extends React.ElementType> = P & { as?: T };
+
+export type PolymorphicPropsWithoutRef<P, T extends React.ElementType> = Merge<
+	React.ComponentPropsWithoutRef<T>,
+	PropsWithAs<P, T>
+>;
+
+export type PolymorphicPropsWithRef<P, T extends React.ElementType> = Merge<
+	React.ComponentPropsWithRef<T>,
+	PropsWithAs<P, T>
+>;
+
+// TODO:
+// - PolymorphicFunctionComponent
+// - PolymorphicVoidFunctionComponent (requires @types/react >=16.9.48)
+
+type PolymorphicExoticComponent<
+	P = {},
+	T extends React.ElementType = React.ElementType
+> = Merge<
+	React.ExoticComponent<P & { [key: string]: unknown }>,
+	{
+		/**
+		 * **NOTE**: Exotic components are not callable.
+		 */
+		<InstanceT extends React.ElementType = T>(
+			props: PolymorphicPropsWithRef<P, InstanceT>,
+		): React.ReactElement | null;
+	}
+>;
+
+export type PolymorphicForwardRefExoticComponent<
+	P,
+	T extends React.ElementType
+> = Merge<
+	React.ForwardRefExoticComponent<P & { [key: string]: unknown }>,
+	PolymorphicExoticComponent<P, T>
+>;
+
+export type PolymorphicMemoExoticComponent<
+	P,
+	T extends React.ElementType
+> = Merge<
+	React.MemoExoticComponent<React.ComponentType<any>>,
+	PolymorphicExoticComponent<P, T>
+>;
+
+export type PolymorphicLazyExoticComponent<
+	P,
+	T extends React.ElementType
+> = Merge<
+	React.LazyExoticComponent<React.ComponentType<any>>,
+	PolymorphicExoticComponent<P, T>
+>;