Replacestring

Replacestring is a string manipulation operation that constructs a new string by replacing occurrences of a given substring with another substring. It is a common utility in programming languages, scripting tools, and text-processing utilities.

The operation can target a single occurrence or all occurrences, depending on the language or function variant. In many languages, the default is to replace all non-overlapping occurrences; some provide a separate function or flag to limit the operation to the first match. The exact behavior may vary when the replacement target is treated as a regular expression rather than a plain substring.

Common parameters include the source text, the target substring to be replaced, and the replacement substring. Options often cover case sensitivity and whether matching should be done on whole substrings or using pattern-based rules. When the replacement target is a regular expression, special characters must be escaped to avoid unintended pattern interpretation.

Implementation notes: performance depends on the length of the input and the number of replacements. In languages with immutable strings, replacestring returns a new string, leaving the original unchanged. If the target substring is empty, behavior can vary; some implementations insert the replacement between each character, others throw an error.

Examples: In pseudocode, result = replacestring(text, "old", "new") replaces all occurrences. In Python, text.replace("old", "new") performs a global replacement. In JavaScript, text.replaceAll("old", "new") replaces all, while text.replace("old", "new") replaces only the first occurrence.

See also: replace function, substitution, regular expressions, string manipulation.