This gives the expected results:

with open(data_file, newline="") as reader:
csvreader = csv.DictReader(reader)
for row in csvreader:
#print(row)
match row[RULE_TYPE]:
case "RANGE":
print("range")
case "MANDATORY":
print("mandatory")
case _:
print("nothing to do")

This:

RANGE = "RANGE"
MANDATORY = "MANDATORY"
with open(data_file, newline="") as reader:
csvreader = csv.DictReader(reader)
for row in csvreader:
#print(row)
match row[RULE_TYPE]:
case RANGE:
print("range")
case MANDATORY:
print("mandatory")
case _:
print("nothing to do")

Gives (and I don't understand why):

SyntaxError: name capture 'RANGE' makes remaining patterns unreachable

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On 8/06/23 10:18 am, Jason Friedman wrote:

SyntaxError: name capture 'RANGE' makes remaining patterns unreachable

The bytecode compiler doesn't know that you intend RANGE
to be a constant -- it thinks it's a variable to bind a
value to.

To make this work you need to find a way to refer to the
value that isn't just a bare name. One way would be to
define your constants using an enum:

class Options(Enum):
RANGE = "RANGE"
MANDATORY = "MANDATORY"

match stuff:
case Options.RANGE:
...
case Options.MANDATORY:
...

--
Greg

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On Thu, 8 Jun 2023 at 08:19, Jason Friedman via Python-list <python-list@python.org> wrote:

This gives the expected results:

with open(data_file, newline="") as reader:
csvreader = csv.DictReader(reader)
for row in csvreader:
#print(row)
match row[RULE_TYPE]:
case "RANGE":
print("range")
case "MANDATORY":
print("mandatory")
case _:
print("nothing to do")

This:

RANGE = "RANGE"
MANDATORY = "MANDATORY"
with open(data_file, newline="") as reader:
csvreader = csv.DictReader(reader)
for row in csvreader:
#print(row)
match row[RULE_TYPE]:
case RANGE:
print("range")
case MANDATORY:
print("mandatory")
case _:
print("nothing to do")

Gives (and I don't understand why):

SyntaxError: name capture 'RANGE' makes remaining patterns unreachable

It's being as clear as it can. When you say "case RANGE:", that is not
a literal, that is a name capture. Check the docs and examples for
case statements for more details.

ChrisA

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

The bytecode compiler doesn't know that you intend RANGE
to be a constant -- it thinks it's a variable to bind a
value to.

To make this work you need to find a way to refer to the
value that isn't just a bare name. One way would be to
define your constants using an enum:

class Options(Enum):
RANGE = "RANGE"
MANDATORY = "MANDATORY"

match stuff:
case Options.RANGE:
...
case Options.MANDATORY:
...

Got it, thank you.

On Wed, Jun 7, 2023 at 6:01 PM Greg Ewing via Python-list < python-list@python.org> wrote:

On 8/06/23 10:18 am, Jason Friedman wrote:

SyntaxError: name capture 'RANGE' makes remaining patterns unreachable

The bytecode compiler doesn't know that you intend RANGE
to be a constant -- it thinks it's a variable to bind a
value to.

To make this work you need to find a way to refer to the
value that isn't just a bare name. One way would be to
define your constants using an enum:

class Options(Enum):
RANGE = "RANGE"
MANDATORY = "MANDATORY"

match stuff:
case Options.RANGE:
...
case Options.MANDATORY:
...

--
Greg

--
https://mail.python.org/mailman/listinfo/python-list

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)