group ... into in C#

Group inside a query and keep querying over the groups.

var commits = new[]
{
    (Author: "ada", Files: 3), (Author: "alan", Files: 1),
    (Author: "ada", Files: 5), (Author: "kurt", Files: 2),
};

// group ... by ... into g continues the query over the groups
var summary =
    from c in commits
    group c by c.Author into g
    orderby g.Sum(c => c.Files) descending
    select $"{g.Key}: {g.Count()} commits, {g.Sum(c => c.Files)} files";

Console.WriteLine(string.Join("\n", summary));

How it works

group c by c.Author into g restarts the query per group.
g.Key, g.Count() and g.Sum(...) summarize each author.
orderby ranks the groups, not the rows.

Keywords and builtins used here

by
descending
from
group
in
into
new
orderby
select
string
var

The run, in numbers

Lines: 14
Characters to type: 413
Tokens: 94
Three-star pace: 85 tpm

At the three-star pace of 85 tokens a minute, this run takes about 66 seconds.

Type this snippet

Step 3 of 3 in Query syntax, step 12 of 17 in LINQ in depth.

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