Implement 'unique' function

Simply takes in a list and returns one back with only unique items, in
the order of first occurrence.

This commit also adds anchor links to headers in the MkDocs website.

core/consts.go

@@ -28,5 +28,6 @@ const (
 	TRUNCATE           = "truncate"
 	SPLIT              = "split"
 	RANGE              = "range"
+	UNIQUE             = "unique"
 	CONFIRM            = "confirm"
 )

core/rsl_func_unique.go

@@ -0,0 +1,21 @@
+package core
+
+import (
+	"fmt"
+	"github.com/samber/lo"
+)
+
+// todo allow string input? to avoid needing to split(input, "") first
+func runUnique(i *MainInterpreter, function Token, args []interface{}) interface{} {
+	if len(args) != 1 {
+		i.error(function, UNIQUE+fmt.Sprintf("() takes 1 argument, got %d", len(args)))
+	}
+
+	switch arr := args[0].(type) {
+	case []interface{}:
+		return lo.Uniq(arr)
+	default:
+		i.error(function, UNIQUE+fmt.Sprintf("() takes an array as its argument, got %s", TypeAsString(args[0])))
+		panic(UNREACHABLE)
+	}
+}

core/rsl_functions.go

@@ -152,6 +152,10 @@ func RunRslNonVoidFunction(
 		assertExpectedNumReturnValues(i, function, functionName, numExpectedReturnValues, 1)
 		validateExpectedNamedArgs(i, function, NO_NAMED_ARGS, namedArgsMap)
 		return runRange(i, function, args)
+	case UNIQUE:
+		assertExpectedNumReturnValues(i, function, functionName, numExpectedReturnValues, 1)
+		validateExpectedNamedArgs(i, function, NO_NAMED_ARGS, namedArgsMap)
+		return runUnique(i, function, args)
 	case CONFIRM:
 		assertExpectedNumReturnValues(i, function, functionName, numExpectedReturnValues, 1)
 		validateExpectedNamedArgs(i, function, NO_NAMED_ARGS, namedArgsMap)

core/testing/split_test.go → core/testing/func_split_test.go

@@ -31,3 +31,13 @@ print(split("Alice      Smith", " +"))
 	assertNoErrors(t)
 	resetTestState()
 }
+
+func TestSplit_CanSplitOnNoSeparater(t *testing.T) {
+	rsl := `
+print(split("Alice", ""))
+`
+	setupAndRunCode(t, rsl)
+	assertOnlyOutput(t, stdOutBuffer, "[A, l, i, c, e]\n")
+	assertNoErrors(t)
+	resetTestState()
+}

core/testing/func_unique_test.go

@@ -0,0 +1,35 @@
+package testing
+
+import "testing"
+
+func TestUnique(t *testing.T) {
+	rsl := `
+print(unique([2, 1, 2, 3, 1, "Alice", 4, 3, 5, 5]))
+`
+	setupAndRunCode(t, rsl)
+	assertOnlyOutput(t, stdOutBuffer, "[2, 1, 3, Alice, 4, 5]\n")
+	assertNoErrors(t)
+	resetTestState()
+}
+
+func TestUnique_Large(t *testing.T) {
+	rsl := `
+a = unique([2 for i in range(1000)])
+print(len(a))
+print(a[0])
+`
+	setupAndRunCode(t, rsl)
+	assertOnlyOutput(t, stdOutBuffer, "1\n2\n")
+	assertNoErrors(t)
+	resetTestState()
+}
+
+func TestUnique_String(t *testing.T) {
+	rsl := `
+print(join(unique(split("Frodo Baggins is a hobbit", "")), ""))
+`
+	setupAndRunCode(t, rsl)
+	assertOnlyOutput(t, stdOutBuffer, "Frod Baginshbt\n")
+	assertNoErrors(t)
+	resetTestState()
+}

docs-web/docs/reference/ref-functions.md

@@ -144,6 +144,22 @@ Are you sure? > n
 Unsure!
 ```
 
+### join
+
+```rsl
+join(input any[], prefix string|int|float|bool?, suffix string|int|float|bool?) -> string
+```
+
+### unique
+
+```rsl
+unique(input any[]) -> any[]
+```
+
+```rsl
+unique([2, 1, 2, 3, 1, 3, 4])  // [2, 1, 3, 4]
+```
+
 ## Time
 
 ### now_date
@@ -243,12 +259,6 @@ replace(input, "Charlie (.*)", "Alice $1")
 "Alice Brown" 
 ```
 
-### join
-
-```rsl
-join(input any[], prefix string|int|float|bool?, suffix string|int|float|bool?) -> string
-```
-
 ### starts_with
 
 ```rsl

docs-web/mkdocs.yml

@@ -31,3 +31,5 @@ markdown_extensions:
   - admonition
   - pymdownx.details
   - pymdownx.superfences
+  - toc:
+      permalink: true # 