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Shorthand way for assigning a single field in a record, while copying the rest of the fields?
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157
Yes, there's a nice way of updating record fields. In GHCi you can do --
> data Foo = Foo ...
Is it possible to have empty RequestParam values use the defaultValue?
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178
You could change the @RequestParam type to an Integer and make it not required. This would all...
Is gcc 4.8 or earlier buggy about regular expressions?
I am trying to use std::regex in a C++11 piece of code, but it appears that the support is a bit buggy. An example:
3 Answe...
YAML Multi-Line Arrays
...uence is an array. So this is the right way to express it:
key:
- string1
- string2
- string3
- string4
- string5
- string6
That's identical in meaning to:
key: ['string1', 'string2', 'string3', 'string4', 'string5', 'string6']
It's also legal to split a single-line array ove...
SQL Server equivalent to MySQL enum data type?
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160
It doesn't. There's a vague equivalent:
mycol VARCHAR(10) NOT NULL CHECK (mycol IN('Useful',...
How does one escape backslashes and forward slashes in VIM find/search?
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151
Same way you escape characters most anywhere else in linuxy programs, with a backslash:
:%s/&...
How to delete object from array inside foreach loop?
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answered Feb 21 '10 at 2:56
prodigitalsonprodigitalson
57.1k77 gold badges8888 silver badges108108 bronze badges
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How does one output bold text in Bash?
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edited Apr 29 '15 at 9:54
gsamaras
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PHP best way to MD5 multi-dimensional array?
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13 Answers
13
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Reorder levels of a factor without changing order of values
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121
Use the levels argument of factor:
df <- data.frame(f = 1:4, g = letters[1:4])
df
# f g
...