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What is the best way to test for an empty string in Go?
...
Both styles are used within the Go's standard libraries.
if len(s) > 0 { ... }
can be found in the strconv package: http://golang.org/src/pkg/strconv/atoi.go
if s != "" { ... }
can be found in the encoding/json package: http://golang.org/src/pkg/encoding/...
What underlies this JavaScript idiom: var self = this?
...his even as the context is changing. It's a technique often used in event handlers (especially in closures).
Edit: Note that using self is now discouraged as window.self exists and has the potential to cause errors if you are not careful.
What you call the variable doesn't particularly matter. va...
Computed read-only property vs function in Swift
...operties for just that: properties; meaning simple values that you can get and/or set. I use functions (or methods) when actual work is being done. Maybe something has to be computed or read from disk or from a database: In this case I use a function, even when only a simple value is returned. That ...
Build an iOS app without owning a mac? [closed]
...ases
iPhone/iPad (iOS) app development
iPhone/iPad (iOS) app development and Publish to iTunes Store
1. iPhone/iPad (iOS) app development
So If you just want to develop iOS apps you don't want to pay anything,
You just need Mac + XCode IDE
Get Mac Mini or Mac Machine
Create Developer Accoun...
Access object child properties using a dot notation string [duplicate]
... answered Nov 8 '11 at 14:39
Andy EAndy E
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Simple basic explanation of a Distributed Hash Table (DHT)
...e now independent nodes in a network.
This gives a lot of fault-tolerance and reliability, and possibly some performance benefit, but it also throws up a lot of headaches. For example, what happens when a node leaves the network, by failing or otherwise? And how do you redistribute keys when a node...
Logical operators (“and”, “or”) in DOS batch
...
You can do and with nested conditions:
if %age% geq 2 (
if %age% leq 12 (
set class=child
)
)
or:
if %age% geq 2 if %age% leq 12 set class=child
You can do or with a separate variable:
set res=F
if %hour% leq 6 se...
TimePicker Dialog from clicking EditText
...( "" + selectedHour + ":" + selectedMinute);
Your missing a + between "" and selected hour, setText methods only take a single string, so you need to concatenate all the parts (the first quotes are likely unnecessary).
eReminderTime.setOnClickListener(new OnClickListener() {
@Override
...
Evaluate expression given as a string
...ied. For example, if you have a pre-defined variable name equal to "David" and you reassign using eval(parse(text = "name") == "Alexander", you will get an error because eval & parse do not return an R expression that can be evaluated.
– Crt
Aug 1 '16 at 22...
Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...