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* examples/c/lexcalc/parse.y: Formatting/comment changes. (line): Don't return a value. Print the result here, which avoids printing a value for lines with an error. (yyerror): Be sure to increment the pointed, not the pointer... * examples/c/lexcalc/lexcalc.test: Check errors. * examples/c/lexcalc/local.mk: Fix a dependency.
Examples in C
This directory contains simple examples of Bison grammar files in C.
Most of them come from the documentation, which should be installed together with Bison. The URLs are provided for convenience.
rpcalc - Reverse Polish Notation Calculator
The first example is that of a simple double-precision Reverse Polish Notation calculator (a calculator using postfix operators). This example provides a good starting point, since operator precedence is not an issue.
Extracted from the documentation: "Reverse Polish Notation Calculator" https://www.gnu.org/software/bison/manual/html_node/RPN-Calc.html
calc - Simple Calculator
This example is slightly more complex than rpcalc: it features infix
operators (1 + 2, instead of 1 2 + in rpcalc), but it does so using a
unambiguous grammar of the arithmetics instead of using precedence
directives (%left, etc.).
mfcalc - Multi-Function Calculator
A more complete C example: a multi-function calculator. More complex than the previous example. Using precedence directives to support infix operators.
Extracted from the documentation: "Multi-Function Calculator: mfcalc". https://www.gnu.org/software/bison/manual/html_node/Multi_002dfunction-Calc.html
lexcalc - calculator with Flex and Bison
The calculator, redux. This time using a scanner generated by Flex.