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reply Vino <vino.bheeman hotmail.com> writes:
Hi All,

  It is possible to store struct in a array ans use the same in 
csvReader e.g.

import std.stdio;
import std.container.array;

void main () {
Array!string a;
struct Layout { string name; int value; double other; }

a.insert(Layout);
auto record =  
uFile.byLineCopy().joiner("\n").csvReader!(Tuple!a[0]))
foreach (record; records)
{
     writeln(record.name);
     writeln(record.value);
     writeln(record.other);
}

From,
Vino.B
Jan 09
next sibling parent Vino <vino.bheeman hotmail.com> writes:
On Tuesday, 9 January 2018 at 13:49:41 UTC, Vino wrote:
 Hi All,

  It is possible to store struct in a array ans use the same in 
 csvReader e.g.

 import std.stdio;
 import std.container.array;

 void main () {
 Array!string a;
 struct Layout { string name; int value; double other; }

 a.insert(Layout);
 auto record =  
 uFile.byLineCopy().joiner("\n").csvReader!(Tuple!a[0]))
 foreach (record; records)
 {
     writeln(record.name);
     writeln(record.value);
     writeln(record.other);
 }

 From,
 Vino.B
Hi All, Was able to find on hot to store a struct in an array, but not able to use that array in csvReader Program: import std.algorithm: joiner; import std.container.array; import std.csv: csvReader; import std.stdio: File, writeln; import std.typecons: Tuple, tuple; void main () { auto fName = "C:\\Users\\bheev1\\Desktop\\Current\\Script\\Others\\Table1.csv"; auto uFile = File(fName, "r"); struct T1 { string Name; string Country; int Age; } Array!T1 T1s; foreach (record; uFile.byLineCopy().joiner("\n").csvReader!(Tuple!T1s)) writeln(record); } Error: C:\D\dmd2\windows\bin\..\..\src\phobos\std\typecons.d(523): Error: template instance parseSpecs!(T1s) cannot use local 'T1s' as parameter to non-global template parseSpecs(Specs...) C:\D\dmd2\windows\bin\..\..\src\phobos\std\typecons.d(635): Error: CTFE failed because of previous errors in injectNamedFields ArrayStruct.d(12): Error: template instance ArrayStruct.main.Tuple!(T1s) error instantiating Failed: ["dmd", "-v", "-o-", "ArrayStruct.d", "-I."] From, Vino.B
Jan 09
prev sibling parent reply thedeemon <dlang thedeemon.com> writes:
On Tuesday, 9 January 2018 at 13:49:41 UTC, Vino wrote:
 Hi All,

  It is possible to store struct in a array ans use the same in 
 csvReader
Sure, you can just pass the type of your struct to csvReader: struct Layout { string name; int value; double other; } auto readArrayOfStructs(string fname) { Array!Layout res; foreach(record; fname.readText.csvReader!Layout('\t')) { res ~= record; } return res; }
Jan 09
parent reply Vino <vino.bheeman hotmail.com> writes:
On Tuesday, 9 January 2018 at 17:00:05 UTC, thedeemon wrote:
 On Tuesday, 9 January 2018 at 13:49:41 UTC, Vino wrote:
 Hi All,

  It is possible to store struct in a array ans use the same in 
 csvReader
Sure, you can just pass the type of your struct to csvReader: struct Layout { string name; int value; double other; } auto readArrayOfStructs(string fname) { Array!Layout res; foreach(record; fname.readText.csvReader!Layout('\t')) { res ~= record; } return res; }
Hi Deemon, Thank you, and sorry for the confusion, the requirement is as below auto reader(T) (Array!T T1s, T fname) { auto uFile = File(fName, "r"); foreach (record; uFile.byLineCopy().joiner("\n").csvReader!(Tuple!T1s)) // receive the type and fetch the record writeln(record); } void main () { auto fName = "C:\\Users\\bheev1\\Desktop\\Current\\Script\\Others\\Table1.csv"; struct T1 { string Name; string Country; int Age; } Array!T1 T1s; reader(fName, T1s); // pass the array Type as a function parameter } From, Vino.B
Jan 09
parent reply Vino <vino.bheeman hotmail.com> writes:
On Tuesday, 9 January 2018 at 17:41:10 UTC, Vino wrote:
 On Tuesday, 9 January 2018 at 17:00:05 UTC, thedeemon wrote:
 On Tuesday, 9 January 2018 at 13:49:41 UTC, Vino wrote:
 Hi All,

  It is possible to store struct in a array ans use the same 
 in csvReader
Sure, you can just pass the type of your struct to csvReader: struct Layout { string name; int value; double other; } auto readArrayOfStructs(string fname) { Array!Layout res; foreach(record; fname.readText.csvReader!Layout('\t')) { res ~= record; } return res; }
Hi Deemon, Thank you, and sorry for the confusion, the requirement is as below auto reader(T) (Array!T T1s, T fname) { auto uFile = File(fName, "r"); foreach (record; uFile.byLineCopy().joiner("\n").csvReader!(Tuple!T1s)) // receive the type and fetch the record writeln(record); } void main () { auto fName = "C:\\Users\\bheev1\\Desktop\\Current\\Script\\Others\\Table1.csv"; struct T1 { string Name; string Country; int Age; } Array!T1 T1s; reader(fName, T1s); // pass the array Type as a function parameter } From, Vino.B
Details For example let say we have 3 struct auto read(T) (T Filename, T ArrayType) { T ArrayType res; foreach (record; Filename.byLineCopy().joiner("\n").csvReader!(T)(Tuple!ArrayType)) foreach(i, T; ColumnTypes) { res[i].insert(record[i]); } } return res; } void main () { struct S1 { } struct S2 { } struct S3 { } Get user input(UI) if(UI == S1) { Array!S1 T1; writeln(read(File1, Array Type)); } From, Vino.B
Jan 09
parent reply thedeemon <dlang thedeemon.com> writes:
On Tuesday, 9 January 2018 at 18:09:58 UTC, Vino wrote:
  It is possible to store struct in a array ans use the same 
 in csvReader
Sure, you can just pass the type of your struct to csvReader:
 Array!T1 T1s;
 reader(fName, T1s); // pass the array Type as a function 
 parameter
First you write a template function that takes an array of some generic type and fills it with records from CSV file: void readData(DataType)(string fname, ref Array!DataType arr) { foreach (record; fname.readText.csvReader!DataType('\t')) { arr ~= record; } } Then you can use it in your main program with different types: struct S1 { string name; string value; int other; } struct S2 { int a; string b; } void main () { ... if (someCondition) { Array!S1 arr1; readData("data1.csv", arr1); } else { Array!S2 arr2; readData("data2.csv", arr2); } } A little advice. Kindly pause and spend an evening reading this book: http://ddili.org/ders/d.en/ Currently your code pieces look like a soup produced by someone who still confuses variables and types, and lacks basic programming skills. Read the book, don't rush with writing broken code.
Jan 09
parent Vino <vino.bheeman hotmail.com> writes:
On Tuesday, 9 January 2018 at 19:05:48 UTC, thedeemon wrote:
 On Tuesday, 9 January 2018 at 18:09:58 UTC, Vino wrote:
  It is possible to store struct in a array ans use the same 
 in csvReader
Sure, you can just pass the type of your struct to csvReader:
 Array!T1 T1s;
 reader(fName, T1s); // pass the array Type as a function 
 parameter
First you write a template function that takes an array of some generic type and fills it with records from CSV file: void readData(DataType)(string fname, ref Array!DataType arr) { foreach (record; fname.readText.csvReader!DataType('\t')) { arr ~= record; } } Then you can use it in your main program with different types: struct S1 { string name; string value; int other; } struct S2 { int a; string b; } void main () { ... if (someCondition) { Array!S1 arr1; readData("data1.csv", arr1); } else { Array!S2 arr2; readData("data2.csv", arr2); } } A little advice. Kindly pause and spend an evening reading this book: http://ddili.org/ders/d.en/ Currently your code pieces look like a soup produced by someone who still confuses variables and types, and lacks basic programming skills. Read the book, don't rush with writing broken code.
Hi Deemon, I agree that my code is broken code and I am a Newbie in the world of programming, the confusion begin when i started writing the second module, and now i was able to find the issue, and the real requirement. The requirement is as below. Program: The below program works. auto reader(MyStruct) (File fname, auto ref MyStruct st) { alias ColumnTypes = AliasSeq!(MyStruct); foreach (record; fname.byLineCopy().joiner("\n").csvReader!(Tuple!ColumnTypes)(null)) { writeln(record[0], record[1], record[2]); } void main () { auto fname = File("C:\\Users\\bheev1\\Desktop\\Current\\Script\\Others\\Table2.csv"); auto Table = baseName(stripExtension(fname)); struct S1 { string Name; string Country; int Age; } S1 Table1s; reader(File(fname), join([Table, "1s"])); } The requirement is as below The function reader should store the data in column wise Array and return the same. Array!<Type has to be taken from ColumnTypes < Name of the array has to be taken from the header data as the CSV file has header Name, Country, Age using records.header) e.g Array!string Name; (records.header[0]); Array!string Country;(records.header[1]); Array!string Age;(records.header[2]); and return the above arrays From, Vino.B
Jan 10