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digitalmars.D - Iterate JSON during compile-time.

reply Tariq Siddiqui <m.tariqsiddiqui gmail.com> writes:
Hello everyone,

I want to iterate over the JSON using CTFE. I have tried both 
std.json and vibe.data.json, but there is no luck. I am not sure 
what I am missing.
```d
import std.stdio;
import std.json;
import std.array;
import vibe.data.json;

void main()
{
	enum string config = `{ "ModelNames": [ "Bank", "Biller", 
"Aggregator" ] }`;
	const auto c1 = parseJSON(config);
	immutable auto c2 = parseJsonString(config);
	
	foreach (key; c1["ModelNames"].array)
		writeln(key.get!string);

	foreach (key; c2["ModelNames"])
		writeln(key.get!string);

	// static foreach (key; c1["ModelNames"].array)
	// 	pragma(msg, key.get!string);

	// static foreach (key; c2["ModelNames"])
	// 	pragma(msg, key.get!string);
}
```
Apr 10 2021
parent Tariq Siddiqui <m.tariqsiddiqui gmail.com> writes:
On Saturday, 10 April 2021 at 14:03:55 UTC, Tariq Siddiqui wrote:

 Hello everyone,

 I want to iterate over the JSON using CTFE. I have tried both 
 std.json and vibe.data.json, but there is no luck. I am not 
 sure what I am missing.
 ```d
 import std.stdio;
 import std.json;
 import std.array;
 import vibe.data.json;

 void main()
 {
 	enum string config = `{ "ModelNames": [ "Bank", "Biller", 
 "Aggregator" ] }`;
 	const auto c1 = parseJSON(config);
 	immutable auto c2 = parseJsonString(config);
 	
 	foreach (key; c1["ModelNames"].array)
 		writeln(key.get!string);

 	foreach (key; c2["ModelNames"])
 		writeln(key.get!string);

 	// static foreach (key; c1["ModelNames"].array)
 	// 	pragma(msg, key.get!string);

 	// static foreach (key; c2["ModelNames"])
 	// 	pragma(msg, key.get!string);
 }
 ```


Thanks to Vladimir, the problem is solved by his advice.

```d
import std.algorithm.iteration;
import std.stdio;
import std.json;
import std.array;
import vibe.data.json;

void main()
{
     enum string config = `{ "ModelNames": [ "Bank", "Biller", 
"Aggregator" ] }`;
     immutable auto c1 = parseJSON(config);
	immutable auto c2 = parseJsonString(config);
	
	static foreach (key; c1["ModelNames"].array.map!(item => 
item).array)
         pragma(msg, key.get!string);

	static foreach (key; c2["ModelNames"].array.map!(item => 
item).array)
		pragma(msg, key.get!string);
}
```
Apr 10 2021