Development method: Getting it to work

The tools that we use to "compile" and "run" our compiler and simulator in nut are: nut31 and nsim31. Both are written in C. nut31 compiles the source in nut into an object code which is executable by nsim31, the n-code virtual machine. The output from nut31 has the default name "a.obj".

nsim31 reads the object code and run it. It also has the system call that supports the compiler, for example "tokeniser", "read stdin". Because some object needs the stdin so nsim31 does not use stdin to name the object file. It reads, by default, the object named "a.obj", so that stdin is free to be used by the use program.

Example 1

let the source program be "nut.txt". To compile it:

c:>nut31 < nut.txt

The output will be "a.obj" which is the nut-compiler. When the compiler is run, it reads input from stdin. Let "t2.txt" be the source program to be compiled by nut-compiler.

c:>nsim31 < t2.txt

The nut-compiler outputs the result to stdout.

Example 2

We want to compile and run "quick.txt", the quicksort program.

c:>nut31 < quick.txt

It will output a.obj. Then run it by:

c:>nsim31

Example 3

We want to use nut-compiler to compile the program "t2.txt" and to run it. First, we compile the nut-compiler:

c:>nut31 < nut.txt

Now the nut-compiler is in "a.obj". We run it to compile "t2.txt". The output is stored in the file "t2.obj".

c:>nsim31 < t2.txt > t2.obj

To run t2.obj, we rename it to "a.obj".

c:>copy t2.obj a.obj

and run it using nsim31:

c:>nsim31

Example 4

We use nut-compiler (nut.txt) to compile the program "t2.txt" and want to run it using the nut-simulator (sim.txt).

First we compile the compiler and use it to compile "t2.txt".

c:>nut31 < nut.txt
c:>nsim31 < t2.txt > t2.obj

Then we compile the simulator and use it to run "t2.obj". The simulator gets its input from stdin.

c:>nut31 < sim.txt
c:>nsim31 < t2.obj

28 June 2006