CS 403 Programming Languages

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CS 403 - Programming Languages

• Class 23
• November 16, 2000

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Todays Agenda

• Augment Chapter 10
• Quick (Re)Introduction to C Templates
• Overview of the Standard Template Library
• Example Code deque stack
• Announcement.
• Programming Assignment, due next week

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C Templates

• Parameterized data types
• Type-safe macros
• Come in two types
• Class Templates
• Function Templates

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Class Templates

• Can specialize class (see listing 1)
• template ltclass Tgt class Stack
• Stackltclass Messagegt
• Or any other type
• Stackltintgt

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Class Template Member Functions

• Method body must be in .h file

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Using a Class Template

• See listing 2
• What is the output?

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Function Templates

• Specialize a function to take polymorphic
  arguments
• Template ltclass Tgt T max(T a, T b)
• But be careful with pointer types
• See listing 3
• What does it print?

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Template Function Specialization

• To fix problem, use type-specific version
• templateltgt char max(char a, char b) return
  strcmp(a, b) gt 0 ? a b

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Standard Template Library (STL)

• Generic Programming
• specify algorithms and data structures that work
  with any data type
• Core Components
• Containers
• Algorithms
• Iterators

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STL Containers

• Data structures that manage a set of memory
  locations
• Doesnt contain many member functions
• Creating, copying, destroying, adding, removing
• No pointers to elements
• Algorithms do the day-to-day stuff

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STL Iterators

• Used to traverse elements of containers
• Uniform set/naming across containers
• Algorithms designed to work with a particular
  iterator category

Random Access
Bi-Directional
Forward
Output
Input
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STL Algorithms

• Decoupled from containers
• Parameterized by iterator types
• Algorithm categories
• Non-mutating sequence operations
• Mutating sequence operations
• Searching and Sorting
• Set Operations
• Heap operations
• Numeric operations
• Miscellaneous

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Orthogonal Component Structure

• So how does this all work together?
• vectorltintgt v(3)v0 7v1 v0 3v2
  v0 v1reverse(v.begin(), v.end())
• So what kind of components are v, v.begin(), and
  reverse?

Algorithm
Iterator
Container
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Example STL deque

• Double-Ended QUEue
• Supports
• Random access to elements
• Constant time insertion removal of elements _at_
  end
• Linear time insertion and removal of elements in
  the middle
• Constant time insertion removal of elements _at_
  beginning
• What role would the template parameter to deque
  fulfill?

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Example STL deque

• Use
• dequeltintgt QQ.push_back(3)Q.push_front(1)Q.i
  nsert(Q.begin() 1, 2)Q2
  0copy(Q.begin(), Q.end(), ostream
  iteratorltintgt(cout, ))
• What does this do?

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Example STL stackltT, Sequencegt

• Adaptor that supports restricted subset of
  Container functionality
• Insertion, removal, and inspection of element at
  the top of the stack
• Does not allow iteration through its elements

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Example STLstackltT, Sequencegt

• Example use
• int main() stackltintgt S S.push(8)
  S.push(7) S.push(4) assert(S.size() 3)
  assert(S.top() 4) S.pop()
  assert(S.top() 7) S.pop() assert(S.top()
  8) S.pop() assert(S.empty())

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Containers

• Sequences
• vector, deque list, slist, bit_vector
• Associative Containers
• set, map, multiset, multimap, hash_set, hash_map,
  hash_multiset, hash_multimap, hash
• String package
• char_traits, basic_string,
• rope
• Container adaptors
• stack, queue, priority_queue, bitset

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Algorithms

• Non-mutating algorithms
• for_each, find,, count, mismatch, equal, search
• Mutating algorithms
• copy, swap, transform, replace, fill, generate,
  remove, unique, reverse, rotate, random_shuffle,
  random_sample, partition, stable_partition,
  sorting, nth_element, binary search, merge, set
  operations heap operations, min and max,
  lexicographical_compare, permutations
• Generalized numeric algorithms
• iota, accumulate, inner_product, partial_sum,
  adjacent_difference, power

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Iterators

• Iterator classes
• istream_iterator
• ostream_iterator
• front_insert_iterator
• back_insert_iterator
• insert_iterator
• reverse_iterator
• reverse_bidirectional_iterator
• raw_storage_iterator
• sequence_buffer