介绍

Eva is the mini language in course Building an Interpreter from scratch, and this is a version implemented in typescript.

Install eva command line tool with following command.

npm i -g @handcraft/eva

You can use eva command to evaluate eva script from different sources.

Use -e argument to execute code directly.

eva -e '(var x 10) (print (* x 15))'
eva -e '(print ((lambda (x) (* x x)) 2))'

Use -f argument to execute local script file.

eva -f test/test.eva
eva -f test/math-test.eva

Otherwise you'll have a interactive shell like node.

eva

> (var x 10)
> (x)
10