Examples with Val water.rapids.Val used on opensource projects

Example 76 with Val

use of water.rapids.Val in project h2o-3 by h2oai.

the class AstTmpAssign method apply.

@Override
public ValFrame apply(Env env, Env.StackHelp stk, AstRoot[] asts) {
    // Note: non-standard evaluation of the first argument! Instead of being
    // executed, it is stringified. This, for example, allows us to write an
    // expression as
    //     (tmp= newid (* frame 3))
    // instead of
    //     (tmp= "newid" (* frame 3))
    // On the other hand, this makes us unable to create dynamic identifiers
    // in Rapids, for example this is invalid:
    //     (tmp= (+ "id" 3) (* frame 3))
    // Right now there is no need for dynamically generated identifiers, since
    // we don't even have proper variables or loops or control structures yet.
    //
    Key<Frame> id = Key.make(env.expand(asts[1].str()));
    Val srcVal = stk.track(asts[2].exec(env));
    Frame srcFrame = srcVal.getFrame();
    Value v = DKV.get(id);
    if (v != null) {
        if (v.get().equals(srcFrame))
            return (ValFrame) srcVal;
        else
            throw new IllegalArgumentException("Temp ID " + id + " already exists");
    }
    Frame dst = new Frame(id, srcFrame._names, srcFrame.vecs());
    // Track new session-wide ID
    return new ValFrame(env._ses.track_tmp(dst));
}