strendswith

Strendswith is a string operation used to determine whether a given string ends with a specified suffix. It is commonly exposed as a dedicated method in many programming languages, providing a simple, readable way to test the final characters of a string.

In different languages, the exact name and parameters vary but the behavior is similar. Python exposes it as str.endswith(suffix[, start[, end]]), where suffix can be a string or a tuple of strings, and start and end define a slice of the string to consider. JavaScript provides String.prototype.endsWith(searchString[, length]), where length limits the portion of the string to inspect. Other languages have analogous helpers, such as Ruby’s end_with? and similar string utilities in standard libraries.

Typical semantics include case sensitivity, since most implementations compare characters exactly. An empty suffix is usually considered to match, returning true. If the string is shorter than the suffix, the result is false. Some implementations support multiple acceptable suffixes, allowing a single call to check against several endings. Handling of multibyte or Unicode characters follows the language’s normal string model.

Examples illustrate common usage. In Python, "report_final.txt".endswith(".txt") evaluates to True. In JavaScript, "license.pdf".endsWith(".pdf") also returns True. These checks are frequently used for validation, file type detection, routing decisions, and parsing tasks where the ending of a string conveys meaning.

Performance is typically efficient, as most language runtimes implement the check with a direct comparison of the relevant tail characters. The method is generally preferred to manual substring comparisons for clarity and maintainability.