dotnet-t4

dotnet-t4 is a command-line tool for processing T4 templates, a general-purpose way to generate text or code files using C#.

It's part of Mono.TextTemplating, a modern open-source reimplementation of the Visual Studio T4 text templating engine.

Example

A T4 template file contains text interleaved with C# or VB.NET code blocks, which is used to generate a template class, then optionally compiled and executed to generate textual output.

Here is an example T4 template, powers.tt. It generates a Markdown table of squares and cubes for numbers up to the value specified by the parameter Max.

<#@ output extension=".md" #> <#@ parameter name="Max" type="int" #> <#@ import namespace="System.Linq" #> # Table of Powers Number | Square | Cube --- | --- <# foreach(int i in Enumerable.Range(2,Max)) {#> <#= i #> | <#= i*i #> | <#= i*i*i #> <#}#>

It can be executed by running t4 powers.tt -p:Max=6, which produces the following powers.md markdown file:

# Table of Powers Number | Square | Cube --- | --- 2 | 4 | 8 3 | 9 | 27 4 | 16 | 64 5 | 25 | 125 6 | 36 | 216

Alternatively, invoking t4 powers.tt -c MyApp.Powers will produce a powers.cs file containing the runtime template class, which you can compile into your app and execute at runtime with new parameter values:

var template = new MyApp.Powers { Session = new Dictionary<string, object> { { "Max", 10 } } }; template.Initialize(); string powersTableMarkdown = template.TransformText();

To learn more about the T4 language, see the Visual Studio T4 documentation.

Usage

t4 is a CLI tool and may be invoked as follows:

t4 [options] [template-file]

The template-file argument is required unless the template text is piped in via stdin.

Option	Description