Language reference#

The reference for Temper the language. To learn it step by step, start with the guide instead.

• Types and values: Boolean, the numbers, String, lists, maps, function types, generators, and how types relate.
• Builtins: the constants, functions, operators, and macros you can use without importing anything, from if and when to @json and test.
• Syntax: how Temper is parsed, with the grammar of each part, semicolon insertion, block lambdas, and strings.
• Modules and files: .temper and literate .temper.md files, modules, and libraries.

Also see the standard library, and what each target language makes of Temper.

These pages began as the reference on temperlang.dev, parts of it generated there from doc comments in the compiler's source; they're hand-edited Markdown now (about these docs). Grammar rules, once drawn as railroad diagrams, are written out as text (Rule := …). Each example ends with a marker that says what it should do: // ✅ it runs (maybe followed by its value), // ❌ it's an error (maybe followed by the errors), and // ⏸️ it isn't run.