Error in template instantiation from D-Cookbook example

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On Friday, 9 February 2018 at 21:31:29 UTC, ShadoLight wrote:
> 	writeln(parse(code));		// to aid with debugging
> 	writeln(convertToD(parse(code)));	// debugging aid
> ..to..
> 	writeln(parse(code)[]);		// to aid with debugging
> 	writeln(convertToD(parse(code))[]);	// debugging aid

The problem becomes apparent once you uncomment one of these and 
paste the offending string ("5 5 + 3 - 2 * 1 + 3 /") in. 
`writeln(convertToD(parse("5 5 + 3 - 2 * 1 + 3 /"))[]);` prints 
the following:

push(5);
push(5);
push(call!+(pop(), pop()));
push(3);
push(call!-(pop(), pop()));
push(2);
push(call!*(pop(), pop()));
push(1);
push(call!+(pop(), pop()));
push(3);
push(call!/(pop(), pop()));

If you look at the definition of call:

	int call(string op)(int a, int b) {
		return mixin("b"~op~"a");
	}

So it takes a string as its sole template argument. The problem 
is that the code in convertToD forgot to add the quotes around 
the operators that are supposed to be passed as strings to call. 
If you modify line 14 from the example you pasted to add these 
quotes to the mixin string, it works:

     code ~= "push(call!"~piece~"(pop(), pop()));\n";

becomes

     code ~= "push(call!\""~piece~"\"(pop(), pop()));\n";

Running the modified code, it prints:

push(5);
push(5);
push(call!"+"(pop(), pop()));
push(3);
push(call!"-"(pop(), pop()));
push(2);
push(call!"*"(pop(), pop()));
push(1);
push(call!"+"(pop(), pop()));
push(3);
push(call!"/"(pop(), pop()));

And `runDslCode!"5 5 + 3 - 2 * 1 + 3 /"();` prints `[5]`.