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How do I use boolean variables in Perl?
...
In Perl, the following evaluate to false in conditionals:
0
'0'
undef
'' # Empty scalar
() # Empty list
('')
The rest are true. There are no barewords for true or false.
share
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Integrate ZXing in Android Studio
...ependencies {
implementation 'com.journeyapps:zxing-android-embedded:3.0.2@aar'
implementation 'com.google.zxing:core:3.2.0'
}
and Gradle does all the magic to compile the code and makes it accessible in your app.
To start the Scanner afterwards, use this class/method:
From the Activity:
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How to hide first section header in UITableView (grouped style)
...hat seems reasonably clean to me. So I'm answering my own question.
Since 0 as the first section header's height doesn't work, I return 1. Then I use the contentInset to hide that height underneath the navigation bar.
Objective-C:
- (CGFloat) tableView:(UITableView *)tableView heightForHeaderInSe...
Remove outline from select box in FF
...he color of the dotted border. So say if you do...
select {
color: rgba(0,0,0,0);
}
Firefox will render the dotted border transparent. But of course your text will be transparent too! So we must somehow display the text. text-shadow comes to the rescue:
select {
color: rgba(0,0,0,0);
text-...
Why does struct alignment depend on whether a field type is primitive or user-defined?
...est = new RefAndTwoInt32Wrappers();
test.text = "adsf";
test.x.x = 0x11111111;
test.y.x = 0x22222222;
Console.ReadLine(); // <=== Breakpoint here
When the breakpoint hits, use Debug + Windows + Memory + Memory 1. Switch to 4-byte integers and put &test in the Address f...
What does “fragment” mean in ANTLR?
...r:
NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS;
fragment DIGITS: '1'..'9' '0'..'9'*;
fragment OCTAL_DIGITS: '0' '0'..'7'+;
fragment HEX_DIGITS: '0x' ('0'..'9' | 'a'..'f' | 'A'..'F')+;
In this example, matching a NUMBER will always return a NUMBER to the lexer, regardless of if it matched "1234", "...
Validate decimal numbers in JavaScript - IsNumeric()
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2908
@Joel's answer is pretty close, but it will fail in the following cases:
// Whitespace strings...
RuntimeWarning: invalid value encountered in divide
...
evadeflow
3,8243030 silver badges3737 bronze badges
answered Apr 16 '14 at 18:05
Yan ZhuYan Zhu
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How to format a float in javascript?
... string, how can I get just 2 digits after the decimal point? For example, 0.34 instead of 0.3445434.
14 Answers
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Finding local IP addresses using Python's stdlib
How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
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