INCOMPLETE RK TO C COMPILER - usage: perl rk.pl < input.rk > output.c

rk.pl

use Text::ParseWords;

print "typedef void *UNTYPED;\n";
print "#define ARGS UNTYPED args[]\n";
print "#define INT __uint128_t\n";
print "#define STR char *\n\n";

my @variables;
my $variable_count = 0;
my @code;
my $lines = 0;
my $cur_func;

while (<>) {

# prerequisites:
# - copy `ex VAR NAME` inside function `FUNC` to `VAR FUNC_NAME` at top of file
# - replace `ex VAR NAME` inside function `FUNC` with `VAR FUNC_NAME`
# - append space to each line
# - append newline

########################
# complex replacements #
########################

s/(?<=\*)(.*?)(?=\n)//g; s/\*/ /g;    # remove comments
s/ +$//g;                             # remove trailing spaces
s/(\w+)\:start/UNTYPED $1(ARGS) {/g;  # replace func:start with "UNTYPED func(ARGS) {"
if (length($1 // '')) {
    $cur_func = $1;
}
s/(\w+)\:end/}/g;                     # replace func:end with }
s/\s*(\$)\s*/$1/g;                    # replace x $ y with x$y
s/(\w)\$(\w)/$1\[$2\]/g;              # replace x$y with x[y]
s/(\w):(\w)/$1_$2/g;                  # globals:foo -> globals_foo

#############
# functions #
#############

while ($_ =~ /(.*?):\s+(.*)/g) {
   s/(.*?):\s+(.*)/$1($2)/g;
}

sub remove_sp {
    join ", ", quotewords('\s+', 1, shift);
}

s/(\([^)]*\))/remove_sp($1)/eg;

#########################
# variable modification #
#########################

s/int /INT /g;
s/str /STR /g;
s/chr /CHR /g;
s/var /UNTYPED /g;

####################
# global variables #
####################

s/ex (\w+) (\w+)/$cur_func\_$2/g;

if (length($1 // '') && (length($2 // ''))) {
    $variables[$variable_count++] = $1 . ' ' . $cur_func . '_' . $2 . ";\n";
}

#############################
# basic syntax modification #
#############################

s/while /while (/g;
s/done/}/g;
s/ do/) {/g;

###########
# cleanup #
###########

s/ +$//g;                             # remove trailing spaces
s/$/;/;                               # append semicolons to generate valid C

} continue {
    $code[$lines++] = $_;
}

print @variables;
print "\n";
print @code;

print "int main(int argc, char **argv) {\n";
print "    return (int) rk(argv);\n";
print "}\n";