Function Name as Function Pointer: A Design Rationale
The equivalence between using a function name as a function pointer and applying the address-of operator to the function name is a curious language design.
Rationale
According to the ANSI C90 Rationale document, this equivalence was introduced to enhance the convenience of function pointers. By allowing function designators to be used interchangeably with pointers, developers gain the flexibility to call functions using shorthand notation or the more conventional pointer syntax.
Implicit Conversion
The language design also includes an implicit conversion between function types and function pointers when used as parameters. However, this conversion is not applicable when a function type is used as a return type. This behavior aims to prevent unintended pointer returns and ensure type safety.
Example
Consider the following code:
typedef bool (*FunType)(int); bool f(int); int main() { FunType a = f; // Equivalent to &f FunType *j(); // Returns function pointer }
In this example, the a variable can be assigned the function pointer for f without using the address-of operator. This shorthand syntax simplifies the code and makes it more readable.
Inconsistency with Arrays
While the equivalence between function names and function pointers is consistent with the way arrays are used in C, it does introduce some inconsistency. For instance, using the name of an array (a) as a pointer (&a) is not allowed, highlighting the special treatment given to functions in this regard.
Conclusion
The equivalence between function names and function pointers was introduced as a design decision to improve the convenience of using function pointers. While this approach provides flexibility, it also introduces some inconsistencies in the language's behavior.
The above is the detailed content of Why are Function Names Equivalent to Function Pointers in C?. For more information, please follow other related articles on the PHP Chinese website!

This article details C function return types, encompassing basic (int, float, char, etc.), derived (arrays, pointers, structs), and void types. The compiler determines the return type via the function declaration and the return statement, enforcing

Gulc is a high-performance C library prioritizing minimal overhead, aggressive inlining, and compiler optimization. Ideal for performance-critical applications like high-frequency trading and embedded systems, its design emphasizes simplicity, modul

This article explains C function declaration vs. definition, argument passing (by value and by pointer), return values, and common pitfalls like memory leaks and type mismatches. It emphasizes the importance of declarations for modularity and provi

This article details C functions for string case conversion. It explains using toupper() and tolower() from ctype.h, iterating through strings, and handling null terminators. Common pitfalls like forgetting ctype.h and modifying string literals are

This article examines C function return value storage. Small return values are typically stored in registers for speed; larger values may use pointers to memory (stack or heap), impacting lifetime and requiring manual memory management. Directly acc

This article analyzes the multifaceted uses of the adjective "distinct," exploring its grammatical functions, common phrases (e.g., "distinct from," "distinctly different"), and nuanced application in formal vs. informal

This article explains the C Standard Template Library (STL), focusing on its core components: containers, iterators, algorithms, and functors. It details how these interact to enable generic programming, improving code efficiency and readability t

This article details efficient STL algorithm usage in C . It emphasizes data structure choice (vectors vs. lists), algorithm complexity analysis (e.g., std::sort vs. std::partial_sort), iterator usage, and parallel execution. Common pitfalls like


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

SublimeText3 Linux new version
SublimeText3 Linux latest version

Notepad++7.3.1
Easy-to-use and free code editor

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

Dreamweaver CS6
Visual web development tools
