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Is null an Object?
...ype null
According to OpenJDKs 12.0.1 javac it is:
true.toString(); // error: boolean cannot be dereferenced
null.toString(); // error: <null> cannot be dereferenced
Where the angle brackets imply that null is of an other than a primitive type. And according to JLS 4.1:
There are tw...
What are the use(s) for tags in Go?
...indJSON(&json); err != nil {
c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
return
}
the binding tag in this example gives hint to gin package that the data sent to API must have user and password fields cause these fields are tagged as required.
So generraly tags are da...
Using the HTML5 “required” attribute for a group of checkboxes?
...'s a bit I pulled together for JQuery users, including a custom validation error message:
$cbx_group = $("input:checkbox[name^='group']");
$cbx_group.on("click", function() {
if ($cbx_group.is(":checked")) {
// checkboxes become unrequired as long as one is checked
$cbx_group.pr...
Passing just a type as a parameter in C#
... at 20:22
500 - Internal Server Error500 - Internal Server Error
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OSError: [Errno 2] No such file or directory while using python subprocess in Django
...ls inside Python code using subprocess.call() which throws the following error:
3 Answers
...
java.lang.IllegalStateException: Cannot (forward | sendRedirect | create session) after response has
...rs is that they think that the call of a forward(), sendRedirect(), or sendError() would magically exit and "jump" out of the method block, hereby ignoring the remnant of the code. For example:
protected void doXxx() {
if (someCondition) {
sendRedirect();
}
forward(); // This is ...
The Difference Between Deprecated, Depreciated and Obsolete [closed]
...ature still works in the current version of the software, but it may raise error messages or warnings recommending an alternate practice.
The Obsolete attribute marks a program entity as one that is no longer recommended for use. Each use of an entity marked obsolete will subsequently generate a wa...
In node.JS how can I get the path of a module I have loaded via require that is *not* mine (i.e. in
...require.resolve('@scope/module/package.json') it throws a MODULE_NOT_FOUND error. I'm in Node 14.4.0, and the module I am trying to resolve has "type": "module" in its package.json with an exports field that does not include package.json. Not sure if that has anything to do with it...
...
How many levels of pointers can we have?
...l Studio 2010 (on Windows 7), you can have 1011 levels before getting this error:
fatal error C1026: parser stack overflow, program too complex
gcc (Ubuntu), 100k+ * without a crash ! I guess the hardware is the limit here.
(tested with just a variable declaration)
...
Remove an element from a Bash array
...te
local aryref="$2[@]" # a necessary step since '${!$2[@]}' is a syntax error
local arycopy=("${!aryref}") # create a copy of the input array
local status=1
for (( i = ${#arycopy[@]} - 1; i >= 0; i-- )); do # iterate over indices backwards
elmt=${arycopy[$i]}
[[ $elmt == $word ]]...