tsi
A simple typescript REPL.
Usage: tsi
Options:
-h, --help Print this help message
-f, --force Force tsi to evaluate code with typescript errors.
-v, --verbose Print compiled javascript before evaluating.
Installation
tsi runs on node.js and can easily be installed through npm.
npm install -g tsi
Building
The bin directory includes the current build of tsi. If you would like to
rebuild it though, just run
npm run-script build
Example
$ tsi
> var square = (x: number) => x * x;
undefined
> square(5);
25
> square('foo');
error TS2081: Supplied parameters do not match any signature of call target.
error TS2087: Could not select overload for 'call' expression.
Caveats
You can't change the type of variable after it's been declared:
$ tsi
> var x = 5;
undefined
> x = 'hi';
error TS2011: Cannot convert 'string' to 'number'.
You can't redeclare variables (in particular, to get around the previous caveat):
$ tsi
> var x = 1;
undefined
> var x = 'hi';
error TS2000: Duplicate identifier 'x'.