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“A lambda expression with a statement body cannot be converted to an expression tree”
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It means that you can't use lambda expressions with a "statement body" (i.e. lambda expressions which use curly braces) in places where the lambda expression needs to be converted to an expression tree (which is for example the ...
How do you set EditText to only accept numeric values in Android?
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@RileyE What do you mean by this? We just started using this for all our numeric inputs and I want to make sure we're not missing something. Thanks!
– Joshua Pinter
Jan 9 '19 at 17:43
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How do I pass data between Activities in Android application?
...the activity is already running, is there need to do startActivity(i); ? I mean, can I make activity A call activity B, and that returns data to activity A ? am I confused ?
– Francisco Corrales Morales
May 8 '14 at 23:25
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What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
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what's the meaning of '=?' in angularJS directive isolate scope declaration?
Does the question mark after equals have special meaning? ie:
1 Answer
1
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How do I sort an NSMutableArray with custom objects in it?
...B.birthDate.
This is rough pseudocode; you will need to flesh out what it means for one date to be "less", "more" or "equal" to another date (such as comparing seconds-since-epoch etc.):
NSComparisonResult compare(Person *firstPerson, Person *secondPerson, void *context) {
if ([firstPerson birth...
Why no generics in Go?
...e proportionate to the complexity, although we continue to think about it. Meanwhile, Go's built-in maps and slices, plus the ability to use the empty interface to construct containers (with explicit unboxing) mean in many cases it is possible to write code that does what generics would enable, if l...
What is SQL injection? [duplicate]
...SQL Injection occurs when the user of an application is able to affect the meaning of database query. This often occurs when arbitary strings from user input are concatenated to create SQL which is fed to the database. For example lets say we had the following code (in PHP, but the same holds true...
adding noise to a signal in python
... signal
import numpy as np
noise = np.random.normal(0,1,100)
# 0 is the mean of the normal distribution you are choosing from
# 1 is the standard deviation of the normal distribution
# 100 is the number of elements you get in array noise
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What's the difference between utf8_general_ci and utf8_unicode_ci?
...e" respectively).
Some Unicode characters are defined as ignorable, which means they shouldn't count toward the sort order and the comparison should move on to the next character instead. utf8mb4_unicode_ci handles these properly.
In non-latin languages, such as Asian languages or languages with...