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Squares

rascal-0.40.17

Synopsis​

Print a list of squares

Examples​

How can we print a list of squares? Here is a solution:

import IO;      ❶  

@synopsis{Print a table of squares using a for loop and single line string templates}
void squares(int n) {
  println("Table of squares from 1 to <n>\n");      ❷  
  for (int I <- [1 .. n + 1])
      println("<I> squared = <I * I>");             ❸  
}

@synopsis{a solution with one multi line string template}
str squaresTemplate(int N)      ❹  
  = "Table of squares from 1 to <N>
    '<for (int I <- [1 .. N + 1]) {>
    '  <I> squared = <I * I><}>";

  • ❶ The IO module is imported since we want to print things using println.

  • ❷ String interpolation is used several times. Here the value of N is inserted in the header message.

  • ❸ The values of I and I * I are inserted in each line that is printed.

  • ❹ Define an alternative implementation squareTemplate that is based on string templates and returns a string value instead of printing the results itself.

Here is how square can be used:

rascal>squares(9);
Table of squares from 1 to 9

1 squared = 1
2 squared = 4
3 squared = 9
4 squared = 16
5 squared = 25
6 squared = 36
7 squared = 49
8 squared = 64
9 squared = 81
ok

squaresTemplate gives a similar result but now as a string:

rascal>squaresTemplate(9);
str: "Table of squares from 1 to 9\n\n  1 squared = 1\n  2 squared = 4\n  3 squared = 9\n  4 squared = 16\n  5 squared = 25\n  6 squared = 36\n  7 squared = 49\n  8 squared = 64\n  9 squared = 81"
---
Table of squares from 1 to 9

  1 squared = 1
  2 squared = 4
  3 squared = 9
  4 squared = 16
  5 squared = 25
  6 squared = 36
  7 squared = 49
  8 squared = 64
  9 squared = 81
---

To get a truly identical result we have to import the IO module and print the value of squaresTemplate:

rascal>import IO;
ok
rascal>println(squaresTemplate(9));
Table of squares from 1 to 9

  1 squared = 1
  2 squared = 4
  3 squared = 9
  4 squared = 16
  5 squared = 25
  6 squared = 36
  7 squared = 49
  8 squared = 64
  9 squared = 81
ok