CS253 HW2: Document Class                

Changes                

Modified the test code to #include <iostream>.                 

Description                

For this assignment, you will write a class called Doc that represents a simple document. This document is a collection of lines of text, indented by varying amounts. Documents can be read or written to files & I/O streams, and manipulated programatically.                 

Methods                

Doc must have the following public methods:                

default constructor

The default ctor creates an empty Doc.

Copy constructor

Assignment operator

Copy all information from another object of the same class.

Destructor

Destroy.

Doc(path)

Same as .read(path), below.

Doc(istream)

Same as .read(istream), below.

.read(path)

Read everything in the file represented by the std::string argument as a document, replacing any existing data. Produce an error message, mentioning the file name, if the file can’t be read. For each line, strip trailing spaces and carriage return ('\r') characters. The newline does not become part of the Doc object. Any remaining leading spaces become the indentation amount for this line. The input line "   x     " must be stored as the number 3 and the string "x". If a tab character ('\t') is read, produce an error.

Leading & trailing (at the start or the end of the document) empty (after stripping trailing space/return) lines are ignored, and do not participate in any other methods.

.read(istream)

Like the previous method, but read from the given input stream.

.write(path)

Write the document to the file represented by the std::string argument. The indentation for each line is written as the appropriate number of spaces. Each line is terminated by a newline, even the last one.

.write(ostream)

Like the previous method, but write to the given output stream.

.add(string)

Add a line to the end of the Doc. It is assumed that the line doesn’t contain a newline. Treat leading spaces as the indentation, which are not stored as part of the string. The trailing space/return stripping of .read(), and ignoring leading/trailing empty lines, must not happen.

.size()

Return a size_t indicating the number of lines in the object.

.empty()

Return true iff the document contains no lines.

.indent(size_t)

Return, as a size_t, the indentation of the line indicated by the argument. The first line is line zero. If the number given is too large to indicate a line, produce an error mentioning the bad line number and how many lines the object has.

.data(size_t)

Return, as a std::string, the part of the line indicated by the argument, without the indentation. The first line is line zero. If the number given is too large to indicate a line, produce an error mentioning the bad line number and how many lines the object has.

The types and names in the method descriptions, above, do not determine the C++ declarations of those methods. They only serve to informally describe what sort of arguments a method might take. You might pass certain arguments by reference, use const, declare return types, etc.                 

Const-correctness, for arguments, methods, and operators, is your job. For example, it must be possible to call .size() on a const object, or to copy a const object to a non-const object.                 

You may define other methods or data, public or private, as you see fit. You may define other classes, as you see fit. However, to use the Doc class, the user need only #include "Doc.h", not any other header files.                 

Hints                

For the ctor and .read() method that take paths, what directory is the file in!? Don’t worry about it. Just take the filename that was given to you, and pass it to ifstream. It will either work or it won’t. If it’s a relative path, then it’s relative to the current directory. If it’s an absolute path, then it’s an absolute path. This is not your problem.                 

Non-Requirements                

Several things are not specified by this assignment. That means that the answer to these questions is “It’s up to you.”

• What is the return type of .add()?
• How should I store the data?
• Should I have one .cc file, or several?

    export STACK_FRAME_LINK_OVERRIDE=ffff-ad921d60486366258809553a3db49a4a

Libraries                

libhw2.a is a library file. It contains a number of *.o (object) files. It must contain Doc.o, but it may also contain whatever other *.o files you need. The CMakeLists.txt shown creates libhw2.a. It does not contain main().                 

To be explicit, the provided CMakeLists.txt does:

• creates Doc.o by compiling Doc.cc
• creates a library libhw2.a from Doc.o
• creates test.o by compiling test.cc
• creates an executable called test by linking test.o with libhw2.a.

The tar file must contain at least all the files required to do this.                 

Testing                

You will have to write a main() function to test your code. Put it in a separate file, and do not make it part of libhw2.a. Particularly, do not put main() in Doc.h or Doc.cc. You will also have to create Doc.h, and put it into hw2.tar. We will test your program by doing something like this:                 

    mkdir a-new-directory
    cd the-new-directory
    tar -x </some/where/else/hw2.tar
    cmake . && make
    cp /some/other/place/test-program.cc .
    g++ -Wall test-program.cc libhw2.a
    ./a.out

We will supply a main program to do the testing that we want. You should do something similar. It’s your choice whether to include your test program in your hw2.tar file. However, cmake . && make must work. If it fails because you didn’t package test.cc, but your CMakeLists.txt requires test.cc, then your build failed, and you get no points. Test your tar file, not just your code.                 

Sample Run                

Here is a sample run, where % is my shell prompt:                 

% cat CMakeLists.txt
cmake_minimum_required(VERSION 3.11)
project(hw2)

# Are we in the wrong directory?
if (CMAKE_SOURCE_DIR MATCHES "[Hh][Ww]([0-9])$")
    if (NOT PROJECT_NAME MATCHES "${CMAKE_MATCH_1}$")
        message(FATAL_ERROR "Building ${PROJECT_NAME} in ${CMAKE_SOURCE_DIR}")
    endif()
endif()

# Using -Wall is required:
add_compile_options(-Wall)

# These compile flags are highly recommended, but not required:
add_compile_options(-Wextra -Wpedantic)

# Optional super-strict mode:
add_compile_options(-fmessage-length=80 -fno-diagnostics-show-option
    -fstack-protector-all -g -O3 -std=c++17 -Walloc-zero -Walloca
    -Wconversion -Wctor-dtor-privacy -Wduplicated-cond
    -Wduplicated-branches -Werror -Wextra-semi -Wfatal-errors
    -Winit-self -Wlogical-op -Wold-style-cast -Wshadow
    -Wunused-const-variable=1 -Wzero-as-null-pointer-constant)

# add_compile_options must be BEFORE add_executable.

# Create the executable from the source file main.cc:
add_library(${PROJECT_NAME} Doc.cc)
add_executable(test test.cc)
target_link_libraries(test ${PROJECT_NAME})

# Create a tar file every time:
add_custom_target(${PROJECT_NAME}.tar ALL COMMAND
    tar -cf ${PROJECT_NAME}.tar *.cc *.h CMakeLists.txt)

% cmake . && make
… cmake output appears here …
… make output appears here …
% cat test.cc
#include "Doc.h"
#include <cassert>
#include <fstream>
#include <iostream>
#include <string>

using namespace std;

int main() {
    ofstream("data") << "\r \r  \n\nPeter  \n   Ray\r \n  Egon  \n \n\r\n";
    Doc d("data");
    assert(!d.empty());
    assert(d.size()==3);
    assert(d.indent(0) == 0);
    assert(d.indent(1) == 3);
    assert(d.indent(2) == 2);
    assert(d.data(0) == "Peter");
    assert(d.data(1) == "Ray");
    assert(d.data(2) == "Egon");

    d.add("   Winston     ");
    assert(d.size() == 4);
    assert(d.indent(3) == 3);
    assert(d.data(3) == "Winston     ");

    d.add("");
    assert(d.size() == 5);
    assert(d.indent(4) == 0);
    assert(d.data(4) == "");
    cout << "Done.\n";

    const Doc vacant;
    assert(vacant.empty() && vacant.size()==0);
    d = vacant;
    assert(d.empty() && d.size()==0);

    return 0;
}
% ./test
Done.

Requirements                

• Error messages must:
  • state the problem (crying “error” alone is not good enough)
  • go to standard error
  • terminate the program.
• An empty line, or a completely empty document, is not an error.
• It must be an compile-time error or warning to ignore the return value of .size(), .empty(), indent(), or data().
• You may not have any using namespace declarations in your header files.
• All copies (copy ctor, assignment operator) are “deep”. Do not share data between copies—that’s not making a copy.
• You may not use any external programs. You may not use system(), fork(), popen(), execl(), execvp(), etc.
• You may not use C-style I/O, such as printf(), scanf(), fopen(), and getchar().
  • Instead, use C++ facilities such as cout, cerr, and ifstream.
• You may not use endl. Use flush if needed.
• You may not use dynamic memory via new, delete, malloc(), calloc(), realloc(), free(), strdup(), etc.
  • It’s ok to implicitly use dynamic memory via containers such as string or vector.
• You may not use the .eof() method.
• No global variables.
• For readability, don’t use ASCII int constants (65) instead of char constants ('A') for printable characters.
• We will compile your code like this: cmake . && make
  • If that generates warnings, you will lose a point.
  • If that generates errors, you will lose all points.
• There is no automated testing/pre-grading/re-grading.
  • Test your code yourself. It’s your job.
  • Even if you only change it a little bit.
  • Even if all you do is add a comment.
  • Test with the CSU compilers, not just your laptop’s compiler.

If you have any questions about the requirements, ask. In the real world, your programming tasks will almost always be vague and incompletely specified. Same here.                 

Tar file                

• The tar file for this assignment must be called: hw2.tar
• It must contain:
  • source files (*.cc), including Doc.cc
  • header files (*.h), including Doc.h
  • CMakeLists.txt, which will create the library file libhw2.a.
• These commands must produce the library libhw2.a:

    cmake . && make

• Your CMakeLists.txt must use at least -Wall when compiling.

How to submit your work:                

In Canvas, check in the file hw2.tar to the assignment “HW2”. It’s due 11:59ᴘᴍ MT Saturday, with a 24-hour late period for a 25% penalty.                 

How to receive negative points:                

Turn in someone else’s work.