Introduction to TOML and Taplo

In the ever-evolving landscape of software development, configuration management plays a crucial role in ensuring that applications run smoothly and efficiently. Among the various formats available for configuration files, TOML (Tom's Obvious, Minimal Language) has emerged as a popular choice due to its simplicity and readability. Designed to be easy to understand and write, TOML provides a clear structure for defining configuration settings, making it an ideal option for developers who prioritize clarity and maintainability.

Taplo is a CLI toolkit that enhances the TOML experience, offering a range of features designed to simplify the process of creating and managing TOML files. One of its standout capabilities is the TOML Language Server Protocol (LSP) support, which allows seamless integration with popular editors like Vim. This means that developers can enjoy features such formatting, querying TOML documents, and real-time validation directly within their preferred coding environment, making the editing process more efficient and enjoyable.

The video below explores how to effectively use the Taplo command line tool for validating and formatting TOML files, specifically from a PowerShell terminal.

To illustrate its functionality, we work with an example document that contains a common error: the omission of quote characters around a string.

Additionally, the video demonstrates how Taplo operates as a language server within the Vim text editor. This integration provides users with real-time error messages, making it easier to identify and correct issues as they work. You will also see how Taplo facilitates seamless formatting of TOML sections, enhancing readability and maintainability

You will find a comprehensive overview of integrating Language Server Protocol (LSP) clients within the Vim text editor at this link. This resource delves into various approaches for implementing LSP support in Vim, examining the strengths and weaknesses of each method. In this blog-post, we have utilized the yegappan-lsp plugin, configured as follows:

    let lspServers = [#{
                \    name: 'taplo',
                \    filetype: ['toml'],
                \    path: 'C:\\Users\\User\\path_to_taplo_exe\taplo.exe',
                \    args: ['lsp','stdio'],
                \ }]

    silent! autocmd User LspSetup call LspAddServer(lspServers)

where the path is the local path to the Taplo binary. The latest binary for your OS can be downloaded from the Github's releases page. In this example we downloaded the file taplo-full-windows-x86.zip, unzipped and placed the binary taplo.exe in a directory included in the Powershell's variable:

   $env:PATH

If you want to get vertical stacked autocomplete as shown in the video above, the following configuration lines should be added to your .vimrc.

    set wildmenu
    set wildmode=full
    set wildoptions=pum,tagfile

This will display your completions vertically, making it easier to navigate through options.