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How can I check if a file exists in Perl?
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Test whether something exists at given path using the -e file-test operator.
print "$base_path exists!\n" if -e $base_path;
However, this test is probably broader than you intend. The code above will generate output if a p...
How can I check for an empty/undefined/null string in JavaScript?
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Testing the length property may actually be faster than testing the string against "", because the interpreter won't have to create a String object from the string literal.
– Vincent Robert
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Maximum size of a element
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Updated 10/13/2014
All tested browsers have limits to the height/width of canvas elements, but many browsers also limit the total area of the canvas element. The limits are as follows for the browsers I'm able to test:
Chrome:
Maximum height/widt...
How to deploy correctly when using Composer's develop / production switch?
...n theory) very handy for scripts that only make sense in development, like tests, fake-data-tools, debugger, etc.
5 Answers...
Where is array's length property defined?
...tuff = stuff;
}
}
public static void main(String[] args) {
int[] test = new int[5];
test[0] = 2;
test[1] = 33;
System.out.println("Length of int[]:\t" + test.length);
String[] test2 = new String[5];
test2[0] = "2";
test2[1] = "33";
System.out.println("Lengt...
Delete first character of a string in Javascript
... shows "oobar"
To remove all 0's at the start of the string:
var s = "0000test";
while(s.charAt(0) === '0')
{
s = s.substring(1);
}
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Cannot open database “test” requested by the login. The login failed. Login failed for user 'xyz\ASP
...ring to something like:
connectionString="Server=.\SQLExpress;Database=IFItest;User ID=xyz;pwd=top$secret"
If you have a user "xyz" with a password of "top$secret" in your database.
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Cross-browser testing: All major browsers on ONE machine
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Contents
Which browsers have to be tested?
Rules of thumb: Which browsers should be included?
Preparation
Windows XP
Windows 7+ (for IE9+)
Browser downloads
Internet Explorer
Firefox
Opera
Chrome
Safari
Adobe Flash Pl...
Which timestamp type should I choose in a PostgreSQL database?
... NULL DEFAULT NOW(),
CHECK(EXTRACT(TIMEZONE FROM my_timestamp) = '0')
);
test=> SET timezone = 'America/Los_Angeles';
SET
test=> INSERT INTO my_tbl (my_timestamp) VALUES (NOW());
ERROR: new row for relation "my_tbl" violates check constraint "my_tbl_my_timestamp_check"
test=> SET timezon...
Package structure for a Java project?
... you have a choice. It's a well-thought out structure that has been battle-tested, and is familiar to many developers.
– Dov Wasserman
Oct 17 '08 at 4:46
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