Crate formatify

Formatify: Dynamic String Formatting Library

Formatify is a Rust library designed for dynamic string formatting. It provides flexible and powerful tools for parsing strings with placeholders, similar to how Git formats commit logs (see Git pretty format), and replacing them with corresponding values. The library excels in handling various placeholder formats and alignment options, ideal for applications requiring adaptable text representation.

Placeholder Formats

Formatify supports several types of placeholders, enabling a wide range of formatting options. Placeholders are defined within a string using a specific syntax, typically denoted by %(key). The library processes these placeholders and replaces them with corresponding values at runtime.

Supported Placeholder Types:

1. Single-Character Placeholders:

   • New Line (%n): Inserts a newline character where %n is placed.
   • Percentage (%%): Escapes and inserts a literal percent sign.

2. Variable Substitution:

   • Syntax: %(key)
   • Description: Replaces this placeholder with the value associated with key in the key_value HashMap.

3. Format Placeholders:

   • Left Alignment:
     • Syntax: %<(width)
     • Description: Aligns the subsequent placeholder to the left within a field of width characters. The placeholder itself is not displayed.
   • Left Alignment with Truncation:
     • Syntax: %<(width,trunc)
     • Description: Similar to left alignment, but truncates the text to fit within the specified width. The placeholder itself is not displayed.
   • Left Alignment with left Truncation:
     • Syntax: %>(width,ltrunc)
     • Description: Similar to left alignment, but left truncates the text to fit within the specified width. The placeholder itself is not displayed.
   • Right Alignment:
     • Syntax: %>(width)
     • Description: Aligns the subsequent placeholder to the right within a field of width characters. The placeholder itself is not displayed.
   • Right Alignment with Truncation:
     • Syntax: %>(width,trunc)
     • Description: Similar to right alignment, but truncates the text to fit within the specified width. The placeholder itself is not displayed.
   • Right Alignment with left Truncation:
     • Syntax: %>(width,ltrunc)
     • Description: Similar to right alignment, but left truncates the text to fit within the specified width. The placeholder itself is not displayed.

Note: In the context of format placeholders, width refers to the total number of characters allocated for the value being formatted. For example, %<(10) aligns the value within a 10-character wide field.

Example Usage:

let mut key_value = HashMap::new();
key_value.insert("name", "Alice".into());
let formatter = Formatify::new();
let formatted_string = formatter.replace_placeholders(&key_value, "Hello, %(name)!");
assert_eq!(formatted_string, "Hello, Alice!");

Public Methods

Public methods utilizing these placeholders include:

• replace_placeholders: Replaces placeholders in a string with values from a HashMap.
• measure_lengths: Calculates the length of strings and placeholders.
• extract_placeholder_keys: Extracts and lists all valid placeholder keys from a string.

For more details on these methods and their usage, refer to the respective method documentation in this module.

Integration and Compatibility

Formatify is designed to be easily integrated into existing Rust projects and works seamlessly with standard data types and collections.

Contribution and Feedback

Contributions to Formatify are welcome. For bug reports, feature requests, or general feedback, please open an issue on the repository’s issue tracker.

Structs

Formatify

Formatify: Main struct for dynamic string formatting.

Traits

PlaceholderFormatter

Trait used to abstract Formatify from a system.