LINQ Query Syntax Buddy

Problem

LINQ queries can be expressed using the query syntax in C#:

var query =
    from x in Enumerable.Range(1, 10)
    where x % 2 == 0
    select x.ToString();

or by chaining extension methods:

var query =
    Enumerable.Range(1, 10)
              .Where(x => x % 2 == 0)
              .Select(x => x.ToString());

While the query syntax is purer and scales far better in terms of readability (especially when queries get justifiably long), it requires restoring to a mixed approach when parts of a query need to materialize some results. For example, to put the results of the above query into an array, one can simply chain a call to ToArray(). When chaining methods, the call fits in naturally:

var array =
    Enumerable.Range(1, 10)
              .Where(x => x % 2 == 0)
              .Select(x => x.ToString())
              .ToArray();

When using the query syntax, one has resort to a mixed approach that doesn't read as natural:

var array = (
        from x in Enumerable.Range(1, 10)
        where x % 2 == 0
        select x.ToString()
    ).ToArray();

Solution

This library provides some helpers that can be used to align better with the query syntax such that the example discussed in the problem section becomes as simple as writing:

var array = Array(
    from x in Enumerable.Range(1, 10)
    where x % 2 == 0
    select x.ToString());

var dict = Dictionary(
    from x in Enumerable.Range(1, 10)
    where x % 2 == 0
    select KeyValuePair.Create(x, x.ToString()));

Usage

Add the following static import:

using static LinqQuerySyntaxBuddy.Enumerable;

To get the results of a query in array, call the Array function with query as its parameter:

var array = Array(
    from x in Enumerable.Range(1, 10)
    where x % 2 == 0
    select x.ToString());

Likewise, to build a dictionary from a query, make sure that the query generates a KeyValuePair<,> sequence and then use that as the argument of the Dictionary function:

var dict = Dictionary(
    from x in Enumerable.Range(1, 10)
    where x % 2 == 0
    select KeyValuePair.Create(x, x.ToString()));

To provide a key comparer, supply it as the first argument and the query as the second:

var dict = Dictionary(StringComparer.Ordinal,
    from x in new[]
    {
        "foo", "bar", "baz", "qux", "quux", "quuz",
        "corge", "grault", "garply", "waldo", "fred",
        "plugh", "xyzzy", "thud",
    }
    select KeyValuePair.Create(x.ToString(), x));

Like Array and Dictionary, there is also List and HashSet.

See the source code for more.