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How to find all serial devices (ttyS, ttyUSB, ..) on Linux without opening them?
What is the proper way to get a list of all available serial ports/devices on a Linux system?
12 Answers
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More elegant way of declaring multiple variables at the same time
...variables with Boolean values is the best way to write your routine (especially if they really have one-letter names :)
Depending on what you're doing, it may make sense to use a dictionary instead. For example, if you want to set up Boolean preset values for a set of one-letter flags, you could d...
Is using a lot of static methods a bad thing?
I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be ...
Proper way to use **kwargs in Python
...*kwargs):
...etc...
this is not true. In the latter case, f can be called as f(23, 42), while the former case accepts named arguments only -- no positional calls. Often you want to allow the caller maximum flexibility and therefore the second form, as most answers assert, is preferable: but ...
How to change collation of database, table, column?
...
You need to either convert each table individually:
ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4
(this will convert the columns just as well), or export the database with latin1 and import it back with utf8mb4.
...
Maven fails to find local artifact
Occasionally maven complains that a particular dependency, which is built and packaged locally, cannot be found in the local repository while building another project that has it as a dependency. We get an error like:
...
Is there a way to make GHC provide the type class constraints of typed holes?
...ng out-of-scope types
(use -fprint-potential-instances to see them all)
• In the expression: show _
In an equation for ‘it’: it = show _
<interactive>:3:6: error:
• Found hole: _ :: a0
Where: ‘a0’ is an ambiguous type variable
• In the first argum...
How to test equality of Swift enums with associated values
...d values.
So if you're on Swift 4.1 or newer, the following will automatically synthesize the necessary methods such that XCTAssert(t1 == t2) works. The key is to add the Equatable protocol to your enum.
enum SimpleToken: Equatable {
case Name(String)
case Number(Int)
}
let t1 = SimpleToke...
How to write inline if statement for print?
... condition:
block
if expression (introduced in Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly ...
json.dumps vs flask.jsonify
...dumps() method will just return an encoded string, which would require manually adding the MIME type header.
See more about the jsonify() function here for full reference.
Edit:
Also, I've noticed that jsonify() handles kwargs or dictionaries, while json.dumps() additionally supports lists and oth...