Cell evaluation fails when done too early after opening

[ggreif]

After opening a worksheet with associated .hs file (Main module) and too soon evaluating a cell, I get:

<interactive>:2:1: Not in scope: `Hyper.displayIO'
<interactive>:3:1: Not in scope: `mooreImg'
<interactive>:5:38: Not in scope: type constructor or class `IO'
<interactive>:5:41:
    Not in scope: type constructor or class `Graphic'

A remedy could be

• disabling evaluation until the interpreter is ready
• delaying submission of evaluation request until the interpreter is ready

[HeinrichApfelmus]

HyperHaskell is currently not very good at finding out when the interpreter is ready. At the moment, it simply waits ~2.4 seconds and hopes for the best.

// FIXME: more accurate indication that the interpreter process is ready
setTimeout(whenReady, 2400)

[HeinrichApfelmus]

I finally managed to do something about this in commit aef5e80 : The interpret now sends a message back to the window to signal that it is ready. Does that help?