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doc/examples/json_pointer.cpp

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+#include <json.hpp>
+
+using json = nlohmann::json;
+
+int main()
+{
+    // correct JSON pointers
+    json::json_pointer p1;
+    json::json_pointer p2("");
+    json::json_pointer p3("/");
+    json::json_pointer p4("//");
+    json::json_pointer p5("/foo/bar");
+    json::json_pointer p6("/foo/bar/-");
+    json::json_pointer p7("/foo/~0");
+    json::json_pointer p8("/foo/~1");
+
+    // error: JSON pointer does not begin with a slash
+    try
+    {
+        json::json_pointer p9("foo");
+    }
+    catch (std::domain_error& e)
+    {
+        std::cout << "domain_error: " << e.what() << '\n';
+    }
+
+    // error: JSON pointer uses escape symbol ~ not followed by 0 or 1
+    try
+    {
+        json::json_pointer p10("/foo/~");
+    }
+    catch (std::domain_error& e)
+    {
+        std::cout << "domain_error: " << e.what() << '\n';
+    }
+
+    // error: JSON pointer uses escape symbol ~ not followed by 0 or 1
+    try
+    {
+        json::json_pointer p11("/foo/~3");
+    }
+    catch (std::domain_error& e)
+    {
+        std::cout << "domain_error: " << e.what() << '\n';
+    }
+}

doc/examples/json_pointer.link

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+<a target="_blank" href="http://melpon.org/wandbox/permlink/9OR6xQ1rRZDA0W94"><b>online</b></a>

doc/examples/json_pointer.output

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+domain_error: JSON pointer must be empty or begin with '/'
+domain_error: escape error: '~' must be followed with '0' or '1'
+domain_error: escape error: '~' must be followed with '0' or '1'