Editor: problem using string args

[walterbender]

I cannot seem to get a string arg to work the the editor. For example, in test-synth, I can use hertz (a number) but when I change the pitch param to string, I get a compile error.

export class ElementTestSynth extends ElementStatement {
    constructor() {
        super('test-synth', 'test synth', { pitch: ['number'], noteValue: ['number'] });
    }
    onVisit(params: { [key: string]: TData }): void {
        const now = Tone.now();
	const noteValue = params['noteValue'] as number;
	const offset = noteValueToSeconds(_state.notesPlayed);
	console.error("TEST SYNTH", params['pitch'], noteValue, now, offset);
        _defaultSynth.triggerAttackRelease(params['pitch'] as number, noteValue + "n", now + offset);
	_state.notesPlayed += 1/noteValue;
    }
}

test-synth pitch:220 noteValue:8
builds successfully

export class ElementTestSynth extends ElementStatement {
    constructor() {
        super('test-synth', 'test synth', { pitch: ['string'], noteValue: ['number'] });
    }
    onVisit(params: { [key: string]: TData }): void {
        const now = Tone.now();
	const noteValue = params['noteValue'] as number;
	const offset = noteValueToSeconds(_state.notesPlayed);
	console.error("TEST SYNTH", params['pitch'], noteValue, now, offset);
        _defaultSynth.triggerAttackRelease(params['pitch'] as string, noteValue + "n", now + offset);
	_state.notesPlayed += 1/noteValue;
    }
}

test-synth pitch:"c4" noteValue:8
build fails