Compilers: Principles and Practice by Pearson

8 Compilers – Principles and Practice

There is statement by statement processing of the source code, but there is no one-time translation

of the whole source code. Each time a statement needs execution, it has to be processed afresh.

This takes time, of course, and shows up as slower execution compared with a compiled program.

How much slower? It could be as slow as 5 to 100 times, depending upon the source language and

implementation details.

For example, consider a small script segment in shell-script – an interpreted, scripting language for

the shell of UNIX/Linux systems:

for f in *.c

do

grep -n "function" $f

done

This script segment ...