Implement fluent interfaces

[etc/vim.git] / README.md

diff --git a/README.md b/README.md
index 152ceefa9109367950da187b4af26da0bf4d5ed8..ed69cb835eafe07da148e13bdfe118514fab0690 100644 (file)
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@@ -342,6 +342,26 @@ In those cases, parentheses are removed when the entire statement fits
 in one line, or if the inner expression doesn't have any delimiters to
 further split on.  Otherwise, the parentheses are always added.
 
+### Call chains
+
+Some popular APIs, like ORMs, use call chaining.  This API style is known
+as a [fluent interface](https://en.wikipedia.org/wiki/Fluent_interface).
+*Black* formats those treating dots that follow a call or an indexing
+operation like a very low priority delimiter.  It's easier to show the
+behavior than to explain it.  Look at the example::
+```py3
+def example(session):
+    result = (
+        session.query(models.Customer.id)
+        .filter(
+            models.Customer.account_id == account_id,
+            models.Customer.email == email_address,
+        )
+        .order_by(models.Customer.id.asc())
+        .all()
+    )
+```
+
 ### Typing stub files
 
 PEP 484 describes the syntax for type hints in Python.  One of the
@@ -589,6 +609,8 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 ### 18.5a0 (unreleased)
 
+* call chains are now formatted according to the [fluent interfaces](https://en.wikipedia.org/wiki/Fluent_interface) style (#67)
+
 * slices are now formatted according to PEP 8 (#178)
 
 * parentheses are now also managed automatically on the right-hand side
@@ -628,6 +650,9 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 
 * fixed crash on dealing with optional parentheses (#193)
 
+* fixed "is", "is not", "in", and "not in" not considered operators for
+  splitting purposes
+
 * fixed crash when dead symlinks where encountered