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Get nth character of a string in Swift programming language
...e values you can use this implementation
Why is this not built-in?
The error message says "see the documentation comment for discussion". Apple provides the following explanation in the file UnavailableStringAPIs.swift:
Subscripting strings with integers is not available.
The concept of...
Unique BooleanField value in Django?
...he pre_save method on django.db.models.BooleanField. Instead of raising an error if another field was True, I made all other fields False if it was True. Also instead of raising an error if the field was False and no other field was True, I saved it the field as True
fields.py
from django.db.mode...
Best way to allow plugins for a PHP application
...();
$args = func_get_args();
if($num_args < 2)
trigger_error("Insufficient arguments", E_USER_ERROR);
// Hook name should always be first argument
$hook_name = array_shift($args);
if(!isset($listeners[$hook_name]))
return; // No plugins have registered this ...
Converting string from snake_case to CamelCase in Ruby
...ant in context (and does need camelize). 'active_record'.constantize gives error, 'active_record'.camelize.constantize returns the constant ActiveRecord, 'active_record'.classify returns the string 'ActiveRecord'. And if you did 'no_class'.camelize.constantize you'd get error (no such constant NoCla...
How to get a reference to a module inside the module itself?
...ight?
– Dima Tisnek
Jan 8 '13 at 22:05
14
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Does R have an assert statement as in python?
a statement that checks if something is true and if not prints a given error message and exits
3 Answers
...
How to get the parents of a Python class?
...
answered Jan 30 '19 at 4:05
PyTisPyTis
52955 silver badges1010 bronze badges
...
How to wait for several Futures?
...hing else.
The difference with for comprehension is that here you get the error of the first to fail, whereas with for comprehension you get the first error in traversal order of the input collection (even if another one failed first). For example:
val f1 = Future { Thread.sleep(1000) ; 5 / 0 }
va...
Scala: What is a TypeTag and how do I use it?
...cala> def createArr[A](seq: A*) = Array[A](seq: _*)
<console>:22: error: No ClassTag available for A
def createArr[A](seq: A*) = Array[A](seq: _*)
^
scala> def createArr[A : ClassTag](seq: A*) = Array[A](seq: _*)
createArr: [A](seq: A*)(...
keytool error :java.io.IoException:Incorrect AVA format
...; when I have been trying to sign the application I have got the following error. Can anyone help me on this issue?
8 Answe...