Beginner guide

1. What StringKit-FP is#

TStringKit is a collection of static functions for everyday text work: cleaning input, splitting strings, converting identifier case, validating common formats, encoding data, approximate comparison, and simple text analysis. It uses Free Pascal RTL/FCL components only.

Start with the static API. The optional string helper is a second spelling of most string-first calls, not a different implementation.

2. Add StringKit-FP to a project#

For an FPC project, put src/ on the unit search path and add StringKit to uses.

fpc -Fupath/to/stringkit-fp/src your_program.pas

In Lazarus, open packages/lazarus/stringkit_fp.lpk, compile it, then choose Use → Add to Project. Alternatively add the repository’s src/ directory under Project Options → Compiler Options → Paths → Other Unit Files.

3. Make the first call#

The first call program converts an identifier and prints:

hello_world

4. Choose static or helper style#

The static style is explicit and works with only StringKit:

Clean := TStringKit.Trim(Input);

Add StringKitHelper when you prefer a pipeline-like spelling:

Clean := Input.Trim;

Both calls use the same library logic. Read Static API vs helper API before enabling selective helper feature flags.

5. Clean and transform text#

Use Trim for surrounding whitespace and CollapseWhitespace for runs inside text. The compiled normalise input program prints Ada Lovelace. Use ToLower, ToUpper, or ToTitleCase for display-oriented changes. For code-like names, use the identifier converters described in Case conversion.

6. Split and join#

Split returns TStringDynArray, declared in the Types unit. The compiled split and join program shows the full uses list and prints a three-item join. This is useful for simple delimited text, not quoted CSV fields.

7. Convert identifier case#

Use ToCamelCase, ToPascalCase, ToSnakeCase, or ToKebabCase when converting a name such as HelloWorld or snake_case. Start with the identifier case program, then see the case conversion guide for acronyms and digits.

8. Validate common input#

IsValidEmail, IsValidURL, IsValidIPv4, IsValidIPv6, and IsValidDate are practical syntax checks. They do not prove that an address exists, a URL is reachable, or input meets every RFC edge case. See Validation.

9. Encode text for the right context#

Use HTMLEncode before inserting text into HTML. Use PercentEncode for URI components and FormURLEncode for HTML form data. URLEncode is intentionally a legacy-compatible form alias. The encoding guide explains the difference.

10. Prefer safe parsing for external input#

When malformed data is normal, prefer TryHexDecode, TryDecode64, and TryFromRoman. They return False and clear the out value on malformed input. See Parsing and Try APIs.

11. Compare similar text#

IsFuzzyMatch can compare close spellings such as colour and color. Its typed TFuzzyMethod selector makes the chosen algorithm explicit. See Fuzzy matching.

12. Analyse readability and text#

CountWords, FleschReadingEase, FleschKincaidGradeLevel, and GenerateNGrams provide lightweight text analysis. The English readability calculations use heuristic syllable counts; they are useful signals, not editorial verdicts. See Text analysis.

13. Where to go next#

Choose a complete task from Recipes, keep the Cheat Sheet as a reminder, and consult Contracts and limitations whenever input format or indexing matters.