Question

An idle question on language design, see “Does C# have a right hand if like Perl”.

For example, in recent C family languages

z = foo ( a, b, c );

a is evaluated, then b, then c, so left-to-right.

z = a ? b : c;

a is evaluated, then either b or c, so left-to-right order.

In Python, you write a conditional expression as

z = b if a else c

so the order is the same – a,then b or c, but it’s not left-to-right.

Strict left-to-right ordering was put into Java to simplify the language; ordering is implementation dependent in C or C++.

Answer 1

Assignment is (sort of) right to left:

int a = b + c;

b+c gets evaluated, then assigned to a.

---

In general, though, the C# designers have purposely tried to keep most things left->right. A great example is LINQ. Here, instead of going with the traditional SQL ordering (SELECT XXX FROM XXX), they purposely reordered the query to be more left->right.

// Note the left->right ordering:
var results = from member in collection where member.element == condition select member;

// Which is equivelent to:
var resultsNonLinq = collection.Where().Select();

This is part of why I like C# – the consistency in the language is very refreshing, especially when compared to some languages like perl where there is purposely many ways of doing simple things.