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When should I use Struct vs. OpenStruct?
....new(:data1, :data2)
n = Newtype.new
C:
typedef struct {
int data1;
char data2;
} newtype;
newtype n;
The OpenStruct class can be compared to an anonymous struct declaration in C. It allows the programmer to create an instance of a complex type.
Ruby:
o = OpenStruct.new(data1: 0, data2:...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
... two queries, one for INSERT and one for UPDATE (as an appropriate join/subselect of course - no need to write your main filter twice)
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How to do what head, tail, more, less, sed do in Powershell? [closed]
...option for reading a text file. You can then filter further:
gc log.txt | select -first 10 # head
gc -TotalCount 10 log.txt # also head
gc log.txt | select -last 10 # tail
gc -Tail 10 log.txt # also tail (since PSv3), also much faster than above option
gc log.txt | more #...
How to remove spaces from a string using JavaScript?
...
split(' ') and join won't remove \n , \t white space chars, another workaround is a.split('').map(c =>c.trim()).join('')
– rab
Apr 18 '19 at 10:40
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Dealing with commas in a CSV file
... s = s.Replace( QUOTE, ESCAPED_QUOTE );
if ( s.IndexOfAny( CHARACTERS_THAT_MUST_BE_QUOTED ) > -1 )
s = QUOTE + s + QUOTE;
return s;
}
public static string Unescape( string s )
{
if ( s.StartsWith( QUOTE ) && s.EndsWith( QUOTE ) )
...
add column to mysql table if it does not exist
...rade_database_1_0_to_2_0()
BEGIN
-- rename a table safely
IF NOT EXISTS( (SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=DATABASE()
AND TABLE_NAME='my_old_table_name') ) THEN
RENAME TABLE
my_old_table_name TO my_new_table_name,
END IF;
-- add a column safely
IF NO...
How to find out where a function is defined?
...ect files for a specific string and tell you which file it is in and which char position it starts at using only basic php.
Hope this helps someone...
<?php
$find="somefunction()";
echo findString('./ProjectFolderOrPath/',$find);
function findString($path,$find){
$return='';
ob_start(...
What is the difference between printf() and puts() in C?
...e (except for the added newline) if the string doesn't contain any control characters (%) but if you cannot rely on that (if mystr is a variable instead of a literal) you should not use it.
So, it's generally dangerous -and conceptually wrong- to pass a dynamic string as single argument of printf...
node.js execute system command synchronously
...2012: How to get STDOUT]
var lib = ffi.Library(null, {
// FILE* popen(char* cmd, char* mode);
popen: ['pointer', ['string', 'string']],
// void pclose(FILE* fp);
pclose: ['void', [ 'pointer']],
// char* fgets(char* buff, int buff, in)
fgets: ['string', ['string', 'int','po...
Maximum length for MySQL type text
...e to the max length of a text field in my MySQL database table. How many characters can a type text field store?
8 Answer...