From 0ad477827f682750dc21f4b130c4e2154d26822c Mon Sep 17 00:00:00 2001
From: John Marshall <jmarshall@hey.com>
Date: Tue, 23 Jul 2024 20:42:56 +1200
Subject: [PATCH] Document some language facilities available in our py3.6
 baseline

---
 doc/developer.rst | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/doc/developer.rst b/doc/developer.rst
index 5bc30660..cefc9eaf 100644
--- a/doc/developer.rst
+++ b/doc/developer.rst
@@ -33,6 +33,24 @@ directories:
    :file:`import.py` about importing.
 
 
+Python language level
+=====================
+
+Pysam currently requires Python 3.6 as a minimum language level.
+For example, this means that the following comparatively recent
+language features and library functions are available for use:
+
+* f-strings
+* ``raise ... from None``
+* :meth:`str.startswith`, :meth:`str.endswith`, :meth:`str.rstrip`, etc
+
+However in particular the the following should not be used in
+pysam source code or infrastructure scripts:
+
+* :meth:`str.removeprefix`, :meth:`str.removesuffix` (new in 3.9)
+* walrus ``:=`` operator (new in 3.8)
+
+
 Importing new versions of htslib and samtools
 =============================================