Repl and playground

You might want to explore Derw in an interactive fashion, and for that there's two tools that are handy: the repl, and the playground.


To access the repl, simply run derw repl.

In the repl, you can enter definitions for imports, types, functions and consts. They will not be evaluated until you use :run or :show. Between each definition, you should enter a blank newline so that it will be parsed. If parsed successfully, the repl will inform you - and if not, it will show you any errors.


run will evaluate functions and constants

> x: void
> x = globalThis.console.log "hi"
Parsed successfully
> :run


show will first evaluate the current repl body, then print the value of the named value provided

> x: number
> x = 1 + 10
Parsed successfully
> :show x


eval can be used to run some Derw code without needing a definition

> :eval 10 + 10
Parsed successfully


And if you forget all the above, you can use help to get a reminder

> :help
Enter some code, followed by a blank newline.
Run the current namespace via :run
And check the values of code via :show <name>
Or evaluate a constant or function with :eval <function> <args>


The playground currently lets you write Derw code, and see the outputted code in any of the target languages. Later on error messages will be added, along with the ability to import packages and run code in the browser.

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