dyaml/examples/yaml_stats/yaml_stats.d

109 lines
2.7 KiB
D

///Example D:YAML application that displays statistics about YAML documents.
import std.stdio;
import std.string;
import dyaml.all;
///Collects statistics about a YAML document and returns them as string.
string statistics(ref Node document)
{
size_t nodes;
size_t scalars, sequences, mappings;
size_t seqItems, mapPairs;
size_t[string] tags;
void crawl(ref Node root)
{
++nodes;
if((root.tag in tags) is null)
{
tags[root.tag] = 0;
}
++tags[root.tag];
if(root.isScalar)
{
++scalars;
return;
}
if(root.isSequence)
{
++sequences;
seqItems += root.length;
foreach(ref Node node; root)
{
crawl(node);
}
return;
}
if(root.isMapping)
{
++mappings;
mapPairs += root.length;
foreach(ref Node key, ref Node value; root)
{
crawl(key);
crawl(value);
}
return;
}
}
crawl(document);
string tagStats = "\nTag statistics:\n";
foreach(tag, count; tags)
{
tagStats ~= format("\n%s : %s", tag, count);
}
return format( "\nNodes: %s" ~
"\n\nScalars: %s" ~
"\nSequences: %s" ~
"\nMappings: %s" ~
"\n\nAverage sequence length: %s" ~
"\nAverage mapping length: %s" ~
"\n\n%s",
nodes, scalars, sequences, mappings,
sequences == 0.0 ? 0.0 : cast(real)seqItems / sequences,
mappings == 0.0 ? 0.0 : cast(real)mapPairs / mappings,
tagStats);
}
void main(string[] args)
{
//Help message
if(args.length == 1)
{
writeln("Usage: yaml_stats [YAML_FILE ...]\n");
writeln("Analyzes YAML files with provided filenames and displays statistics.");
return;
}
//Print stats about every document in every file.
foreach(file; args[1 .. $])
{
writeln("\nFile ", file);
writeln("------------------------------------------------------------");
try
{
auto loader = Loader(file);
size_t idx = 0;
foreach(ref document; loader)
{
writeln("\nDocument ", idx++);
writeln("----------------------------------------");
writeln(statistics(document));
}
}
catch(YAMLException e)
{
writeln("ERROR: ", e.msg);
}
}
}