Description

The Strings.h library is a compact, header-only C++ string utilities library split across two namespaces: strings_utilities (number → text conversion + rounding) and strings (character classification, tokenization, trimming, filtering, replacements and other common string transformations). It bundles a wide set of small, focused helpers that are immediately useful for CLI tools, data-cleaning scripts, and quick string processing during prototyping.

This is a drop-in header for rapid development: lots of ready-made helpers for counting characters/tokens, trimming, reversing, filtering digits/letters/specials/punctuations/operations/brackets, replacing text (with optional case-insensitive modes), and converting numbers to English words (with decimal support).

Technologies Used

  • Language: C++ (ISO C++)
  • Standard Library headers: <string>, <cctype>, <cmath>, <vector>
  • C++ features & idioms: namespaces, recursion (for number-to-text), string manipulation, std::vector-based tokenization, small utility-style functions

Functionality / Features

  • Number → Text: convertNumToTxt(double, short) — high-level converter that:
    • handles negative numbers
    • rounds to requested precision
    • converts integer and decimal parts to words (e.g., -12.34 → Negative Twelve Point Thirty Four).
  • Character classification & simple predicates (strings)
    • isVow, isLtr, isSpecial, isPunc, isOper, isBracket — small character tests (vowels, letters, special symbols, punctuation, operators, brackets).
    • isStrPalindrome — checks whether a string is palindromic.
  • Case & casing helpers
    • capAllLtrs, lowAllLtrs — uppercase/lowercase all characters.
    • capAllTkns, lowAllTkns — change case for all tokens except delimiters.
    • capTknFstLtr, lowTknFstLtr — change first letter of each token.
    • invChrCase, invStrCase — invert case for a char or whole string.
  • Counting utilities
    • getVowCnt, getCapLtrCnt, getSmlLtrCnt, getLtrCnt, getNonLtrCnt, getSpcCnt, getChrCnt, getDigCnt — counts for various character classes and occurrences.
  • Tokenization & tokens helpers
    • getNumOfTkns(string, char) and overload for string delimiter — count tokens.
    • getVctOfTkns(string, char) and overload for string delimiter — return vector tokens.
    • revTknsSeq — reverse token order.
  • Trimming & simple filters
    • trmRgt, trmLft, trm — trim characters from sides (defaults to space).
    • remDigs, keepDigs, remLtrs, keepLtrs, remSpecials, keepSpecials, remPuncs, keepPuncs, remOpers, keepOpers, remBrackets, keepBrackets, remChr, keepChr — remove/keep based on character-class or a single char.
  • Merging & replacements
    • mrgVct(vector<string>&, delimiter) and mrgArr — join tokens into a single string with delimiter.
    • replaceAll, replaceCnt — replace occurrences globally or up to a specified count, with optional case-insensitive mode.
    • replaceAllTkns — replace token-equal matches (word-level replace) with delimiter control and case-insensitive option.

Implementation Highlights

  • Recursive number-to-text (numToTxtCore) — A clear and compact recursive approach that breaks down large numbers into hundred/thousand/million/billion chunks and maps smaller ranges to literal arrays; used by convertNumToTxt to produce human-friendly text for integer and decimal parts.
  • Decimal-aware conversion (convertNumToTxt) — Rounds the number to requested precision, separates integer and fractional parts, and converts fractional digits as a separate number (it prints “Point” followed by the word form of the fractional digits).
  • Consistent filtering functions — A full set of keep/remove helpers that let you quickly strip or preserve classes of characters; useful for sanitizing or extracting subsets of a string (digits only, letters only, punctuation only, etc.).
  • Tokenization flexibility — Supports both single-character and string delimiters, returning a std::vector<std::string>; also provides token-counting and token-merging helpers for the common token pipeline.
  • Case-insensitive replace — replaceAll and replaceCnt implement a case-insensitive mode by working on a lowercase copy and mapping positions back to the original string for replacement, allowing correct replacement sizes in the original-cased string.
  • Small, focused functions — Each helper does one thing and returns a new string; this makes the library easy to pick and insert into small projects.

Conclusion

  • This library showcases practical engineering of small utilities that make day-to-day development faster.
  • It demonstrates careful thought about user-facing formatting (number→text), data cleaning, and text processing pipelines.

How to Use

  1. Download the header file from the section below.
  2. Include it in your C++ project using #include "...", with the appropriate path between the double quotes.

Source Code

You can find the source code for this header here.

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