pushcalc - push parser with Bison

This directory contains pushcalc, the traditional calculator, implemented as a push parser.

Traditionally Bison is used to create so called “pull parsers”: the user invokes the parser once, which repeatedly calls (pulls) the scanner until the input is drained.

This example demonstrates the “push parsers”: the user calls scanner to fetch the next token, passes (pushes) it to the parser, and repeats the operation until the input is drained.

This example is a straightforward conversion of the ‘calc’ example to the push-parser model.