hcl2: add strlen function and update docs. (#14463)

.changelog/14463.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+jobspec: Added `strlen` HCL2 function to determine the length of a string
+```

jobspec2/functions.go

@@ -81,6 +81,7 @@ func Functions(basedir string, allowFS bool) map[string]function.Function {
 		"slice":           stdlib.SliceFunc,
 		"sort":            stdlib.SortFunc,
 		"split":           stdlib.SplitFunc,
+		"strlen":          stdlib.StrlenFunc,
 		"strrev":          stdlib.ReverseFunc,
 		"substr":          stdlib.SubstrFunc,
 		"timeadd":         stdlib.TimeAddFunc,

website/content/docs/job-specification/hcl2/functions/collection/length.mdx

@@ -1,15 +1,15 @@
 ---
 layout: docs
 page_title: length - Functions - Configuration Language
-description: The length function determines the length of a collection or string.
+description: The length function determines the length of a collection.
 ---
 
 # `length` Function
 
-`length` determines the length of a given list, map, or string.
+`length` determines the length of a given list, map, or tuple.
 
-If given a list or map, the result is the number of elements in that collection.
-If given a string, the result is the number of characters in the string.
+If given a list, map, or tuple, the result is the number of elements in that
+collection.
 
 ## Examples
 
@@ -20,21 +20,4 @@ If given a string, the result is the number of characters in the string.
 2
 > length({"a" = "b"})
 1
-> length("hello")
-5
 ```
-
-When given a string, the result is the number of characters, rather than the
-number of bytes or Unicode sequences that form them:
-
-```shell-session
-> length("👾🕹️")
-2
-```
-
-A "character" is a _grapheme cluster_, as defined by
-[Unicode Standard Annex #29](http://unicode.org/reports/tr29/). Note that
-remote APIs may have a different definition of "character" for the purpose of
-length limits on string arguments; a Nomad provider is responsible for
-translating Nomad's string representation into that used by its respective
-remote system and applying any additional validation rules to it.

website/content/docs/job-specification/hcl2/functions/string/strlen.mdx

@@ -0,0 +1,35 @@
+---
+layout: docs
+page_title: strlen - Functions - Configuration Language
+description: The strlen function determines the length of a string.
+---
+
+# `strlen` Function
+
+`strlen` determines the length of a given string.
+
+```hcl
+strlen(string)
+```
+
+## Examples
+
+```shell-session
+> length("hello")
+5
+```
+
+When given a string, the result is the number of characters, rather than the
+number of bytes or Unicode sequences that form them:
+
+```shell-session
+> length("👾🕹️")
+2
+```
+
+A "character" is a _grapheme cluster_, as defined by
+[Unicode Standard Annex #29](http://unicode.org/reports/tr29/). Note that
+remote APIs may have a different definition of "character" for the purpose of
+length limits on string arguments; a Nomad provider is responsible for
+translating Nomad's string representation into that used by its respective
+remote system and applying any additional validation rules to it.

website/data/docs-nav-data.json

@@ -1322,6 +1322,10 @@
                     "title": "split",
                     "path": "job-specification/hcl2/functions/string/split"
                   },
+                  {
+                    "title": "strlen",
+                    "path": "job-specification/hcl2/functions/string/strlen"
+                  },
                   {
                     "title": "strrev",
                     "path": "job-specification/hcl2/functions/string/strrev"