Computer Knowledge

Programming Languages and Compilers

2,284 Questions

Programming languages and compilers involve the rules, syntax, and semantics used to write and execute software programs. Key areas include scripting languages, object oriented concepts, and parsing algorithms like top down parsers. Practice these computer science questions to build proficiency for technical and computer knowledge exams.

Object oriented languagesScripting languagesCompilers and parsersProgramming syntax

Programming Languages and Compilers Questions

Multiple choice

Macro languages & their associated processors represent a distinct form of _____.

  1. programming languages

  2. register counter

  3. location counter

  4. instruction counter
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Macro languages allow programmers to define shorthand for sequences of instructions, which are then expanded by a macro processor. This system provides a way to extend a base language, making it a specialized form of programming language. Unlike counters, which track addresses or values, macro languages focus on code abstraction and generation.

Multiple choice

Parsing is of two types: 1. top down parsing, and 2. ___________.

  1. system parsing

  2. programming parsing

  3. bottom up parsing

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In compiler theory, parsing is the process of determining the grammatical structure of a sequence of tokens. The two primary strategies for this are top-down parsing, which builds the parse tree from the root down to the leaves, and bottom-up parsing, which starts from the leaves and works up to the root. These two methods cover the vast majority of parsing algorithms used in computer science.

Multiple choice

The synthesis phases are: 1._________________, and 2. code generation.

  1. storage allocation

  2. lexical analysis

  3. semantic analysis

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A compiler is divided into analysis and synthesis phases. The synthesis phase is responsible for taking the analyzed source code and producing the target machine code, which involves storage allocation for variables and the actual generation of instructions. Lexical and semantic analysis are part of the analysis phase, which occurs before synthesis.

Multiple choice

The task(s) of complier is/are ______________.

  1. to convert high level language into machine level language.

  2. to convert high level language into assembly language

  3. to convert assembly language into machine level language

  4. all of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The primary definition of a compiler is a program that translates high-level language (HLL) source code into machine-level language (object code). While some compilers may output assembly language as an intermediate step, the ultimate task that distinguishes a compiler from an assembler is the conversion from a high-level abstraction to a machine-executable format. Option C describes an assembler, not a compiler.

Multiple choice

Which of the following is/are correct about NSLog() in Objective C?

  1. It provides the format specific to the strings.

  2. It is used to denote an object.

  3. It specifies the new value should be sent -retain on assignment and the old value sent release.

  4. It specifies the new value should be sent -copy on assignment and the old value sent release.

  5. It returns the class and memory address of the object.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

NSLog() uses format specifiers to indicate substitution tokens, just like the C standard library printf() function.

Multiple choice

Which of the following is correct about 'retain' attribute in Objective C property?

  1. Its is used to retain the assigned value and release the previously set value.

  2. It makes the compiler NOT check what other threads are executing over the value at the same time.

  3. It is used to create automatically the setter and the getter methods for the property.

  4. The “retain” property is needed when the attribute is a pointer to an object.

  5. Both 1 and 4
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

These are correct statements about 'retain' attribute in Objective C property.

Multiple choice

Which of the following statements is false regarding NULL pointer in Objective C?

  1. The NULL pointer can not be accessible by memory address.

  2. A NULL pointer does not have any memory pointer.

  3. int main () { int *ptr = NULL;NSLog(@"The value of ptr is : %xn", ptr ); return 0; } is the correct syntax for NULL pointer.

  4. The NULL pointer is a constant with a value of zero defined in several standard libraries.

  5. None of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

All are correct statements about NULL pointer n Objective C.

Multiple choice

Which of the following is incorrect about dealloc method in Objective C?

  1. The dealloc method is called on an object when it is being removed from memory.

  2. This method is called automatically by the runtime.

  3. The dealloc method is not called on objects, if garbage collection is enabled.

  4. The [super dealloc] is used to ask the superclass to do its cleanup. If one does not do this, the object will not be removed.

  5. This method is used to set initial values for the instance variables.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is true about initial method, dealloc() is used to delete the memory objects.

Multiple choice

Unix is written in ______.

  1. BASIC

  2. FORTRAN

  3. C

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Unix was famously rewritten in the C programming language in 1973, which made it highly portable compared to earlier operating systems written in assembly.