I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.
https://justine.storage.googleapis.com/emulator625.mp4
Cosmopolitan makes it easy to build and maintain programming languages,
since it abstracts system call #ifdef toil, so you can focus on vision.
Here's an example of a language that isn't turing complete, weighing in
at <1,000 lines of modern C, intended to help with testing libc / libm:
.1 .2 + .3 - abs epsilon < assert
pi sqrt pi sqrt * pi - abs epsilon < assert
-.5 rint dup 0 = assert signbit assert
-.5 nearbyint dup 0 = assert signbit assert
-.5 ceil dup 0 = assert signbit assert
-.5 trunc dup 0 = assert signbit assert
-.5 round -1 = assert
-.5 floor -1 = assert
0 signbit ! assert
CALCULATOR.COM pays homage to CALC.EXE recently removed from Windows 10.
Microsoft should bundle this app instead. It too is roughly 100kb, works
just fine w/ command prompt, and portable since it runs on Mac/Linux/BSD
too while bundling even more features than the calculator on Google.com.
It should be possible to run CALCULATOR.COM on Android and iOS too, just
in case anyone needs a backend pipe driven framework, for graphical user
interfaces of calculators. Sadly we haven't tried it since we don't know
how to run software on telephones so the system call support is a priori
Justine Tunney