RosettaCodeData/Task/Read-a-configuration-file/D/read-a-configuration-file-2.d
2023-07-01 13:44:08 -04:00

40 lines
1.4 KiB
D

import std.stdio, std.string, std.conv, std.regex, std.algorithm;
auto reNameValue = ctRegex!(`^(\w+)\s*=?\s*(\S.*)?`);// ctRegex creates regexp parser at compile time
// print Config members w/o hardcoding names
void PrintMembers(Config c)
{
foreach(M; __traits(derivedMembers, Config))
writeln(M ~ ` = `, __traits(getMember, c, M));
}
void main(in string[] args /* arg[0] is EXE name */) {
auto cfg = new Config;
auto f = args[1].File;// open config given in command line
foreach (line; f.byLineCopy.map!(s => s.strip).filter!(s => !s.empty && s[0] != '#' && s[0] != ';')) {// free loop from unnecessary lines
auto m = matchFirst(line, reNameValue);
if (m.empty) { writeln(`Wrong config line: ` ~ line); continue; }
switch(m[1].toUpper) {
case `FULLNAME`: cfg.FullName = m[2]; break;
case `FAVOURITEFRUIT`: cfg.FavouriteFruit = m[2]; break;
case `NEEDSPEELING`: cfg.needsPeeling = (m[2].toUpper != `FALSE`); break;
case `SEEDSREMOVED`: cfg.seedsRemoved = (m[2].toUpper != `FALSE`); break;
case `OTHERFAMILY`: cfg.otherFamily = split(m[2], regex(`\s*,\s*`)); break;// regex allows to avoid 'strip' step
default:
writeln(`Unknown config variable: ` ~ m[1]);
}
}
PrintMembers(cfg);
}
class Config
{
string FullName;
string FavouriteFruit;
bool needsPeeling;
bool seedsRemoved;
string[] otherFamily;
}