On Sunday, 8 July 2018 at 19:22:32 UTC, Timoses wrote:
On Sunday, 8 July 2018 at 18:46:31 UTC, vino.B wrote:
Hi All,
Request you help, in the below code we pass the function
"Testfun" as a parameter to another function "process" in
order for the function "process" to work we have to specify
the type of the parameter that is passed to the function "(T
function(string, int) coRoutine, string Test, int Size) ", so
now how do we pass a function whose parameter would be dynamic
and the type is unknown.
void process(T)(T function(string, int) coRoutine, string
Test, int Size) {
This would templetize the return type of the coRoutine, thus
within that function you could do
T returnedValue = coRoutine(string.init, int.init);
alias scRType = typeof(coRoutine(string.init, int.init));
Eg:
Run1 : process(&Testfun, Test, Size);
void process(T ...)(T function(string, int) coRoutine, string
Test) {
alias scRType = typeof(coRoutine(string.init, int.init));
Run2 : process(&Testfun, Test, Size, Str1);
void process(T)(T function(string, int, string) coRoutine,
string Test, int Size, string Str1) {
alias scRType = typeof(coRoutine(string.init, int.init,
string.int));
Run3 : process(&Testfun, Test);
void process(T)(T function(string, string) coRoutine, string
Test, int Size) {
alias scRType = typeof(coRoutine(string.init));
PFresult.get = coRoutine(args);
Some what like this
auto Testfun (string FFs, int Size) { return tuple(FFs, Size);
}
void process(T ...)(T function(T args) coRoutine, T args) {
This would mean that if you pass a function that returns for
example an int, it must also
- take an int as argument
- and process has to accept another int
e.g.
process((int i) => i+1, 3);
if T would be (int, string) you would have to pass something
like
process((int i, string s) {
return AliasSeq!(int, string); }, // error: not even
sure how to express this
3, "hello");
where I'm not sure how to express the return type of (int,
string)... Does anybody know this? Would the Tuple Dip make
this possible?
(https://forum.dlang.org/post/p3bdp1$2b4e$1...@digitalmars.com)
alias scRType = typeof(coRoutine(T.init));
PFresult.get = coRoutine(T);
void main() {
string Test ="C:\\Temp\\BACKUP1"; int Size = 1;
process(&Testfun, Test, Size);
}
Code : Working
import std.stdio: writeln;
import std.container.array;
import std.typecons: tuple;
import std.parallelism: taskPool;
auto Testfun (string FFs, int Size) { return tuple(FFs, Size);
}
void process(T)(T function(string, int) coRoutine, string
Test, int Size) {
alias scRType = typeof(coRoutine(string.init, int.init));
auto PFresult = taskPool.workerLocalStorage!scRType();
PFresult.get = coRoutine(Test, Size);
foreach(i; PFresult.toRange) { writeln(i[][]); }
}
void main() {
string Test ="C:\\Temp\\BACKUP1"; int Size = 1;
process(&Testfun, Test, Size);
}
From,
Vino.B
I suggest taking a look at
https://dlang.org/phobos/std_traits.html .
E.g. ReturnType and Parameters:
int func() { return 3; }
assert(is(ReturnType!func == int));
void gunc(int i, double j) {}
import std.meta : AliasSeq;
assert(is(Parameters!gunc == AliasSeq!(int, double)));
Perhaps you could tell us what your goal is. People here might
come up with a nice solution. Why do you feel like having to
use templated functions in the first place? That is, what is
the generic goal of the functions you are trying to define?
Hi Timoses,
We are converting a Power shell script to D in phased manner;
the PS script has many functions and we converted few function to
D in Phase 1.
Phase 1:
Structure of the Program
Main -> Thread Manager->CoFunction1(Fs1,2,3,4,5)
Main -> Thread Manager->CoFunction2(Fs1,2,3,4,5)
The thread manager will call the Cofunctions and the function
gets executed on “N” of file systems each of size 5-10 TB.
The function that we transformed all has the same number of
parameters (3) and the type was same (string, string, int), so we
wrote a static thread manager as below
void ptManager (T)(T function(string, string, int) coRoutine,
Array!string Dirlst, string Step, int Size) {
alias scRType = typeof(coRoutine(string.init, string.init,
int.init));
auto PFresult = taskPool.workerLocalStorage!scRType();
ReturnType!coRoutine rData;
foreach (string FFs; parallel(Dirlst[0 .. $],1)) {
PFresult.get ~= coRoutine(FFs.strip, Step); }
foreach(i; PFresult.toRange) { writeln(i[][]); }
}
void main () {
ptManager(&function1, Fn1Dirlst, Step, Size);
ptManager(&function2, Fn2Dirlst, Step, Age);
}
Phase 2:
In phase 2 we are transferring few more function to the existing
D code, and these functions has variable number of parameter and
different type eg: Function3(string, string, string),
Function(string, int, string, int).
Initially I tried to re-write the ptManager function for each
type of function which ended with 8 ptManager functions, Eg :
ptManager1(string, string, int), ptManager2(string, string,
string), ptManager3(string,int), so now trying as to whether we
can use 1 ptManager function which can process function with “N”
of parameter and types to process all the function, hence trying
to implement the Variadic function. Hence request your help and
suggestion to achieve this.
Command Parameter to all the functions:
Array!string Dirlist : This parameter will contain the the Fs
names
File logF: This parameter is used to store the outoput
File logE: This parameter is used to store the Error Information.
Rest of the function has variable parameters/type.
From,
Vino.B