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StringBuilder vs String concatenation in toString() in Java
...blic <init>()V //public Appc()
.limit stack 2
.limit locals 2
met001_begin: ; DATA XREF: met001_slot000i
.line 12
aload_0 ; met001_slot000
invokespecial java/lang/Object.<init>()V
.line 13
ldc "no name"
astore_1 ; met001_slot001
...
Extract a substring according to a pattern
...
Here are a few ways:
1) sub
sub(".*:", "", string)
## [1] "E001" "E002" "E003"
2) strsplit
sapply(strsplit(string, ":"), "[", 2)
## [1] "E001" "E002" "E003"
3) read.table
read.table(text = string, sep = ":", as.is = TRUE)$V2
## [1] "E001" "E002" "E003"
4) substring
This assumes sec...
Or versus OrElse
... [1] int32 b,
[2] bool CS$4$0000)
IL_0000: nop
IL_0001: ldnull
IL_0002: stloc.0
IL_0003: ldc.i4.3
IL_0004: stloc.1
IL_0005: ldloc.0
IL_0006: ldnull
IL_0007: ceq
IL_0009: ldloc.0
IL_000a: callvirt instance string [mscorlib]System.Object::ToSt...
Should a return statement be inside or outside a lock?
...2
.locals init (
[0] int32 CS$1$0000,
[1] object CS$2$0001)
L_0000: ldsfld object Program::sync
L_0005: dup
L_0006: stloc.1
L_0007: call void [mscorlib]System.Threading.Monitor::Enter(object)
L_000c: call int32 Program::GetValue()
L_0011: stloc.0
L_...
'is' versus try cast with null check
...g) o;
}
This translates to the following IL:
IL_0000: nop
IL_0001: ldstr "test"
IL_0006: stloc.0 // o
IL_0007: ldloc.0 // o
IL_0008: isinst System.String
IL_000D: ldnull
IL_000E: cgt.un
IL_0010: stloc.1
IL_0011: ldloc.1
IL_0012: brfalse....
Batch File; List files in directory, only filenames?
...f tokens^=* %%i in ('where .:*')do %%~nxi
Output:
file_0003.xlsx
file_0001.txt
file_0002.log
where .:*
Output:
G:\SO_en-EN\Q23228983\file_0003.xlsx
G:\SO_en-EN\Q23228983\file_0001.txt
G:\SO_en-EN\Q23228983\file_0002.log
For recursively:
where /r . *
Output:
G:\SO_en-EN\Q23228983\file_0...
Any reason not to use '+' to concatenate two strings?
...myl2
>>> cProfile.run("UsePlus()")
5 function calls in 0.001 CPU seconds
Ordered by: standard name
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.001 0.001 0.001 0.001 <pyshell#1376>:1(UsePlus)
1 0.000 0.000 ...
How to make a valid Windows filename from an arbitrary string?
...dFileNameChars = new char[] { '"', '<', '>', '|', '\0', '\x0001', '\x0002', '\x0003', '\x0004', '\x0005', '\x0006', '\a', '\b', '\t', '\n', '\v', '\f', '\r', '\x000e', '\x000f', '\x0010', '\x0011', '\x0012', '\x0013', '\x0014', '\x0015', '\x0016', '\x0017', '\x0018', '\x0019'...
What is the difference between Ruby 1.8 and Ruby 1.9
...in Ruby.
What's changed?
Single character strings.
Ruby 1.9
irb(main):001:0> ?c
=> "c"
Ruby 1.8.6
irb(main):001:0> ?c
=> 99
String index.
Ruby 1.9
irb(main):001:0> "cat"[1]
=> "a"
Ruby 1.8.6
irb(main):001:0> "cat"[1]
=> 97
{"a","b"} No Longer Supported
R...
How can I output leading zeros in Ruby?
...
Use the % operator with a string:
irb(main):001:0> "%03d" % 5
=> "005"
The left-hand-side is a printf format string, and the right-hand side can be a list of values, so you could do something like:
irb(main):002:0> filename = "%s/%s.%04d.txt" % ["dirname", ...