GRACE LANGUAGE-COMPILER

We're building a compiler for our new language, named Grace, using Flex and Bison.

To simply compile the parser, use the make file, by running:

make

(It throws warnings for the string literals ("var", "id" etc.))

It creates an executable file grace_parser, which you can execute to test any file for its grammar.

IMPORTANT: If you want to use grace.c (to test the tokenizing, with ./grace), make sure that the main() in grace_lexer.l is not commented out. It's, by default, commented out, because the linker doesn't work if the two object files have both a main().

More detailed guide

To create the grace.c file:

flex -o grace.c grace_lexer.l

To create the compiler executable:

gcc grace.c -o grace

To test it using the .gra files:

./grace <path-to-.gra-file>

For example:

./grace ~/Grace_Examples/Hello.gra

Now for the Syntax Analysis:

We create the grace_parser.y file, that contains the rules for the Syntax Analysis. We create the grace_parser.tab.c and grace_parser.tab.h files with bison

bison -d grace_parser.y

or

bison -H grace_parser.y

We cannot compile it yet, because it will complain for the missing yylex(), so we create the object file grace_parser.tab.o and we link it with grace.o.

gcc -c grace_parser.tab.c

gcc -c grace.c

Linking them:

gcc grace_parser.tab.o grace.o utils.c -o grace_parser

(If only grace_parser.y has a main(), the linking will work)