Mercurial > repos > other > SevenLanguagesInSevenWeeks
annotate 1-Ruby/logic-irb.output @ 44:6347bacb3be7
Add more notes about the DSL while I think about it
Note: Several things don't make sense
| author | IBBoard <dev@ibboard.co.uk> |
|---|---|
| date | Mon, 18 Sep 2017 20:53:36 +0100 |
| parents | e5b84cc7bc29 |
| children |
| rev | line source |
|---|---|
| 8 | 1 logic.rb(main):001:0> #! /usr/bin/env ruby |
| 2 logic.rb(main):002:0* | |
| 3 logic.rb(main):003:0* x = 4 | |
| 4 => 4 | |
| 5 logic.rb(main):004:0> | |
| 6 logic.rb(main):005:0* # "if" block is "if… end" - no "then" required | |
| 7 logic.rb(main):006:0* if x == 4 | |
| 8 logic.rb(main):007:1> puts "x equals 4" | |
| 9 logic.rb(main):008:1> end | |
| 10 x equals 4 | |
| 11 => nil | |
| 12 logic.rb(main):009:0> | |
| 13 logic.rb(main):010:0* # Python- and Perl-like following logic also works | |
| 14 logic.rb(main):011:0* puts "x equals 4" if x == 4 | |
| 15 x equals 4 | |
| 16 => nil | |
| 17 logic.rb(main):012:0> puts "x equals 4" unless x != 4 | |
| 18 x equals 4 | |
| 19 => nil | |
| 20 logic.rb(main):013:0> | |
| 21 logic.rb(main):014:0* # Negation has many forms. | |
| 22 logic.rb(main):015:0* # Simple logic: | |
| 23 logic.rb(main):016:0* if x != 5 | |
| 24 logic.rb(main):017:1> puts "x not equal 5" | |
| 25 logic.rb(main):018:1> end | |
| 26 x not equal 5 | |
| 27 => nil | |
| 28 logic.rb(main):019:0> | |
| 29 logic.rb(main):020:0* # Two options on negation | |
| 30 logic.rb(main):021:0* if !(x == 5) | |
| 31 logic.rb(main):022:1> puts "x not equal 5" | |
| 32 logic.rb(main):023:1> end | |
| 33 x not equal 5 | |
| 34 => nil | |
| 35 logic.rb(main):024:0> | |
| 36 logic.rb(main):025:0* if not x == 5 | |
| 37 logic.rb(main):026:1> puts "x not equal 5" | |
| 38 logic.rb(main):027:1> end | |
| 39 x not equal 5 | |
| 40 => nil | |
| 41 logic.rb(main):028:0> | |
| 42 logic.rb(main):029:0* # "unless" blocks instead of "if" | |
| 43 logic.rb(main):030:0* unless x != 4 | |
| 44 logic.rb(main):031:1> puts "x equal 4" | |
| 45 logic.rb(main):032:1> else | |
| 46 logic.rb(main):033:1* puts "x not equals 4" | |
|
12
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
47 logic.rb(main):034:1> end |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
48 x equal 4 |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
49 => nil |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
50 logic.rb(main):035:0> |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
51 logic.rb(main):036:0* # "then" is optional, except in single line statement |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
52 logic.rb(main):037:0* if x == 4 then puts "x equal 4" end |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
53 x equal 4 |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
54 => nil |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
55 logic.rb(main):038:0> if x == 4 then |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
56 logic.rb(main):039:1* puts "x equal 4" |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
57 logic.rb(main):040:1> end |
| 8 | 58 x equal 4 |
| 59 => nil | |
|
12
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
60 logic.rb(main):041:0> if x == 4 |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
61 logic.rb(main):042:1> puts "x equal 4" |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
62 logic.rb(main):043:1> end |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
63 x equal 4 |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
64 => nil |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
65 logic.rb(main):044:0> # The following line gives: |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
66 logic.rb(main):045:0* # logic.rb:…: syntax error, unexpected tIDENTIFIER, expecting keyword_then or ';' or '\n' |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
67 logic.rb(main):046:0* # if x == 4 puts "x equal 4" end |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
68 logic.rb(main):047:0* # |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
69 logic.rb(main):048:0* # if x == 4 puts "x equal 4" endlogic.rb(main):048:0# |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
70 logic.rb(main):048:0# |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
71 logic.rb(main):048:0# |
|
e5b84cc7bc29
Update logic script re: "then" in "if else" statements
IBBoard <dev@ibboard.co.uk>
parents:
8
diff
changeset
|
72 => nil |