[libgpiod][PATCH 5/8] bindings: python: examples: consistency cleanup

[Kent Gibson <warthog618@gmail.com>]

A collection of minor changes to be more consistent with other examples:
 - capitalize comments
 - add line offset to value outputs
 - drop comma from edge event outputs
 - improve behaviour if run on a platform that does not match the
   example configuration
 - use with to cleanup request in toggle_line_value.py

Signed-off-by: Kent Gibson <warthog618@gmail.com>
---
 .../python/examples/async_watch_line_value.py | 15 ++++----
 bindings/python/examples/get_line_value.py    | 13 ++++---
 bindings/python/examples/toggle_line_value.py | 34 +++++++------------
 bindings/python/examples/watch_line_value.py  | 19 +++++------
 4 files changed, 35 insertions(+), 46 deletions(-)

diff --git a/bindings/python/examples/async_watch_line_value.py b/bindings/python/examples/async_watch_line_value.py
index ed09ec9..ea8314f 100755
--- a/bindings/python/examples/async_watch_line_value.py
+++ b/bindings/python/examples/async_watch_line_value.py
@@ -19,12 +19,8 @@ def edge_type(event):
     return "Unknown"
 
 
-def async_watch_line_value():
-    # example configuration - customise to suit your situation
-    chip_path = "/dev/gpiochip0"
-    line_offset = 5
-
-    # assume a button connecting the pin to ground,
+def async_watch_line_value(chip_path, line_offset):
+    # Assume a button connecting the pin to ground,
     # so pull it up and provide some debounce.
     with gpiod.request_lines(
         chip_path,
@@ -40,7 +36,7 @@ def async_watch_line_value():
         poll = select.poll()
         poll.register(request.fd, select.POLLIN)
         while True:
-            # other fds could be registered with the poll and be handled
+            # Other fds could be registered with the poll and be handled
             # separately using the return value (fd, event) from poll()
             poll.poll()
             for event in request.read_edge_events():
@@ -51,4 +47,7 @@ def async_watch_line_value():
 
 
 if __name__ == "__main__":
-    async_watch_line_value()
+    try:
+        async_watch_line_value("/dev/gpiochip0", 5)
+    except OSError as ex:
+        print(ex, "\nCustomise the example configuration to suit your situation")
diff --git a/bindings/python/examples/get_line_value.py b/bindings/python/examples/get_line_value.py
index ab733df..f3ca13b 100755
--- a/bindings/python/examples/get_line_value.py
+++ b/bindings/python/examples/get_line_value.py
@@ -9,19 +9,18 @@ import gpiod
 from gpiod.line import Direction
 
 
-def get_line_value():
-    # example configuration - customise to suit your situation
-    chip_path = "/dev/gpiochip0"
-    line_offset = 5
-
+def get_line_value(chip_path, line_offset):
     with gpiod.request_lines(
         chip_path,
         consumer="get-line-value",
         config={line_offset: gpiod.LineSettings(direction=Direction.INPUT)},
     ) as request:
         value = request.get_value(line_offset)
-        print(value)
+        print("{}={}".format(line_offset, value))
 
 
 if __name__ == "__main__":
-    get_line_value()
+    try:
+        get_line_value("/dev/gpiochip0", 5)
+    except OSError as ex:
+        print(ex, "\nCustomise the example configuration to suit your situation")
diff --git a/bindings/python/examples/toggle_line_value.py b/bindings/python/examples/toggle_line_value.py
index 46e52f9..e0de8fb 100755
--- a/bindings/python/examples/toggle_line_value.py
+++ b/bindings/python/examples/toggle_line_value.py
@@ -16,21 +16,11 @@ def toggle_value(value):
     return Value.INACTIVE
 
 
-def print_value(value):
-    if value == Value.ACTIVE:
-        print("Active")
-    else:
-        print("Inactive")
-
-
-def toggle_line_value():
-    # example configuration - customise to suit your situation
-    chip_path = "/dev/gpiochip0"
-    line_offset = 5
-
+def toggle_line_value(chip_path, line_offset):
+    value_str = {Value.ACTIVE: "Active", Value.INACTIVE: "Inactive"}
     value = Value.ACTIVE
 
-    request = gpiod.request_lines(
+    with gpiod.request_lines(
         chip_path,
         consumer="toggle-line-value",
         config={
@@ -38,14 +28,16 @@ def toggle_line_value():
                 direction=Direction.OUTPUT, output_value=value
             )
         },
-    )
-
-    while True:
-        print_value(value)
-        time.sleep(1)
-        value = toggle_value(value)
-        request.set_value(line_offset, value)
+    ) as request:
+        while True:
+            print("{}={}".format(line_offset, value_str[value]))
+            time.sleep(1)
+            value = toggle_value(value)
+            request.set_value(line_offset, value)
 
 
 if __name__ == "__main__":
-    toggle_line_value()
+    try:
+        toggle_line_value("/dev/gpiochip0", 5)
+    except OSError as ex:
+        print(ex, "\nCustomise the example configuration to suit your situation")
diff --git a/bindings/python/examples/watch_line_value.py b/bindings/python/examples/watch_line_value.py
index 42fc0bd..841bf40 100755
--- a/bindings/python/examples/watch_line_value.py
+++ b/bindings/python/examples/watch_line_value.py
@@ -12,18 +12,14 @@ from gpiod.line import Bias, Edge
 
 def edge_type(event):
     if event.event_type is event.Type.RISING_EDGE:
-        return "Rising "
+        return "Rising"
     if event.event_type is event.Type.FALLING_EDGE:
         return "Falling"
     return "Unknown"
 
 
-def watch_line_value():
-    # example configuration - customise to suit your situation
-    chip_path = "/dev/gpiochip0"
-    line_offset = 5
-
-    # assume a button connecting the pin to ground,
+def watch_line_value(chip_path, line_offset):
+    # Assume a button connecting the pin to ground,
     # so pull it up and provide some debounce.
     with gpiod.request_lines(
         chip_path,
@@ -37,13 +33,16 @@ def watch_line_value():
         },
     ) as request:
         while True:
-            # blocks until at least one event is available
+            # Blocks until at least one event is available
             for event in request.read_edge_events():
                 print(
-                    "offset: %d, type: %s, event #%d"
+                    "line: %d  type: %-7s  event #%d"
                     % (event.line_offset, edge_type(event), event.line_seqno)
                 )
 
 
 if __name__ == "__main__":
-    watch_line_value()
+    try:
+        watch_line_value("/dev/gpiochip0", 5)
+    except OSError as ex:
+        print(ex, "\nCustomise the example configuration to suit your situation")
-- 
2.41.0