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Can I make a not submit a form?
...on is a container in HTML. That allows you to place things like images or tables (not sure why you'd do this, but you could) etc while input doesn't support that. There is a difference between the two, and each one has their appropriate use case.
– R0MANARMY
...
Get local IP address
...xistence of the route to the destination according to the system's routing table and setting the local endpoint accordingly. The last part seems to be undocumented officially but it looks like an integral trait of Berkeley sockets API (a side effect of UDP "connected" state) that works reliably in b...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...ow_add=True in the constructor, the datetime referenced by my_date is "immutable" (only set once when the row is inserted to the table).
With auto_now=True, however, the datetime value will be updated every time the object is saved.
This was definitely a gotcha for me at one point. For reference, ...
Best way to create custom config options for my Rails app?
...ral application configuration that doesn't need to be stored in a database table, I like to create a config.yml file within the config directory. For your example, it might look like this:
defaults: &defaults
audiocast_uri_format: http://blablalba/blabbitybla/yadda
development:
<<: *...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...s and dynamic
programming language runtimes) that
rely heavily on hash tables with
string keys. Without interning,
checking that two different strings
are equal involves examining every
character of both strings. This is
slow for several reasons: it is
inherently O(n) in the length o...
List of standard lengths for database fields
I'm designing a database table and once again asking myself the same stupid question: How long should the firstname field be?
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Has anyone actually implemented a Fibonacci-Heap efficiently?
... (In the line typedef relaxed_heap<Vertex, IndirectCmp, IndexMap> MutableQueue, change relaxed to fibonacci.) I first forgot to compile with optimizations, in which case Fibonacci and binary heaps perform about the same, with Fibonacci heaps usually outperforming by an insignificant amount. ...
Expansion of variables inside single quotes in a command in Bash
...positional arguments. The following invocation is better -- it's not exploitable:
script='echo "arg 1 is: $1"'
/bin/sh -c "$script" -- "$myvar"
Note the use of single ticks in the assignment to script, which means that it's taken literally, without variable expansion or any other form of interpre...
Flexbox: center horizontally and vertically
...ms are stacked vertically:
#container {
display: flex; /* establish flex container */
flex-direction: column; /* make main axis vertical */
justify-content: center; /* center items vertically, in this case */
align-items: center; /* center items horizontally, in this ...
How to handle click event in Button Column in Datagridview?
... using this exact example for a dgv with two columns. One column that's editable and the 2nd with a remove buttton. I click all over the dgv and the event only fires off when I click on the button.
– Luminous
Aug 22 '14 at 14:04
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