[Crystal]: New comments

analyzer-comments/crystal/ameba/convention.md

@@ -6,4 +6,4 @@ Which means this code doesn't follow general [code style][code style] convention
 While this type of issue generally doesn't affect the way code _executes_, it can hurt
 readability or the performance of automated tools such as documentation generators or test runners.
 
-[code style]: https://crystal-lang.org/reference/latest/conventions/coding_style.html
+[code style]: https://crystal-lang.org/reference/latest/conventions/coding_style.html

analyzer-comments/crystal/ameba/warning.md

@@ -1,8 +1,7 @@
 # Ameba warning
 
-**Line %{lineno}** :  %{message} was reported by Ameba.
+**Line %{line_number}** :  %{message} was reported by Ameba.
 
 There is an issue in the code that could lead to a bug or error in the program.
 While this error might not be _severe_, it could lead to more severe issues in the future.
 It is recommend the problem be addressed before proceeding further.
-

analyzer-comments/crystal/crystal-hunter/true_false.md

@@ -0,0 +1,15 @@
+# do not compare boolean values to true or false
+
+Comparing boolean values to true or false is redundant.
+Using `==` will generate a boolean value, so it is unnecessary to compare it to another hardcoded boolean value.
+If wanting to flip the boolean value, use the `!` operator.
+
+```crystal
+# Rather than:
+some_bool == true
+some_bool == false
+
+# Consider:
+some_bool
+!some_bool
+```

analyzer-comments/crystal/gigasecond/pow.md

@@ -0,0 +1,3 @@
+# use 1e9 not math pow
+
+Consider writing `%{value}` as `1e9`.

analyzer-comments/crystal/leap/do_not_use_if_statement.md

@@ -0,0 +1,3 @@
+# do not use if statement
+
+Consider converting the `if`-statement(s) into a single expression using the `&&` and `||` operators.

analyzer-comments/crystal/leap/use-is-divisable_by.md

@@ -0,0 +1,14 @@
+# Modulo
+
+Modulo comparisons is perfectly valid within Crystal, but a more readable way to compare the remainder of a division is with the [divisible_by?][divisible_by] method.
+For example:
+
+```crystal
+# Rather than:
+number % 2 == 0
+
+# Consider:
+number.divisible_by?(2)
+```
+
+[divisible_by]: https://crystal-lang.org/api/latest/Int.html#divisible_by%3F%28num%29%3ABool-instance-method

analyzer-comments/crystal/navigation-computer/to_i.md

@@ -11,4 +11,4 @@ But when defining a [number literal][int], it is more idiomatic to use the `_i{b
 500034214414_i64
 ```
 
-[int]: https://crystal-lang.org/reference/latest/syntax_and_semantics/literals/integers.html
+[int]: https://crystal-lang.org/reference/latest/syntax_and_semantics/literals/integers.html

analyzer-comments/crystal/sieve/do_not_use_div_rem.md

@@ -1,9 +1,9 @@
-# do not use `%` or `/`
+# do not use `%%` or `/`
 
 Like the instructions mention, the purpose of this exercise is to build a Sieve of Eratosthenes without the use of operations such as division or modulo division.
 Please refer to the [Wikipedia link][wikipedia] for a description of the algorithm.
 
 Building the Sieve of Eratosthenes in an immutable language such as Crystal may feel a bit unnatural,
 but it is a beautiful algorithm invented more than two millennia ago that is worth learning and implementing.
 
-[wikipedia]: https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
+[wikipedia]: https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes

analyzer-comments/crystal/two-fer/string_concatenation.md

@@ -1,6 +1,7 @@
 # string concatenation
 
-String concatenation is perfectly valid within Crystal, but a more common way to compose a string is with [string interpolation][interpolation]. For example:
+String concatenation is perfectly valid within Crystal, but a more common way to compose a string is with [string interpolation][interpolation].
+For example:
 
 ```crystal
 # Rather than:

analyzer-comments/crystal/wellingtons-weather-station/do_not_use_if_statement.md

@@ -0,0 +1,3 @@
+# do not use if statement
+
+Consider converting the `if`-statement(s) into a single expression using parentheses(`()`) to control the order of evaluation.