FindandReplace

Find and replace is a common text processing operation in which a search pattern is located within a text and replaced with a user-specified string. It is a fundamental feature in word processors, text editors, integrated development environments, and batch-processing tools. The operation can target entire documents, selections, single lines, or multiple files and is often accompanied by options that refine matches and replacements.

Typical capabilities include case sensitivity, whole-word matching, regular expressions for complex patterns, backreferences in the replacement, and search direction. Advanced implementations may support multiline patterns, Unicode, and escape sequences. Some tools also offer batch or multi-file search and replace, atomic operations, and undo/redo integration.

Common interfaces include keyboard shortcuts (for example, Ctrl+H to open the dialog in many applications or :%s in vi-like editors) and command-line forms (for example, sed 's/pat/repl/g' file). Replacements may be literal strings or evaluated expressions, and some editors allow scripts or macros to automate sequences of replacements.

Historically, find and replace originated in line editors and became a staple in Unix tools like sed and awk. Modern editors integrate rich GUI dialogs and regex engines, while programming languages provide built-in functions such as Python's re.sub, JavaScript's string replace, and Java's Pattern and Matcher classes.

Limitations include potential unintended changes when patterns are too broad, performance issues on very large files, and problems with encoding or special characters. Good practice involves backing up data, using incremental searches, and validating replacements.