diff --git a/prelude.ld b/prelude.ld
index 05938a1..726c706 100644
--- a/prelude.ld
+++ b/prelude.ld
@@ -18,7 +18,7 @@ fn join
 fn neg?
 fn atan/2
 fn mod
-fn assoc?
+fn assoc & ?
 fn dict
 fn get
 fn unbox
@@ -370,14 +370,26 @@ fn ws? {
 	(_) -> false
 }
 
+fn strip {
+	"Removes punctuation from a string, removing all instances of ,.;:?!"
+	("{x},{y}") -> strip ("{x}{y}")
+	("{x}.{y}") -> strip ("{x}{y}")
+	("{x};{y}") -> strip ("{x}{y}")
+	("{x}:{y}") -> strip ("{x}{y}")
+	("{x}?{y}") -> strip ("{x}{y}")
+	("{x}!{y}") -> strip ("{x}{y}")
+	(x) -> x
+}
+
 fn words {
 	"Takes a string and returns a list of the words in the string. Strips all whitespace."
 	(str as :string) -> {
-		let raw_strs = split (str, " ")
-		fn joiner (list, str) -> if eq? (str, "") 
+		let no_punct = strip (str)
+		let strs = split (no_punct, " ")
+		fn worder (list, str) -> if empty? (str) 
 			then list 
 			else append (list, str)
-		fold (joiner, raw_strs, [])
+		fold (worder, strs, [])
 	}
 }
 
@@ -502,6 +514,11 @@ fn inv/0 {
 	(x as :number) -> div/0 (1, x)
 }
 
+fn inv/safe {
+	"Returns the inverse of a number: 1/n or `div/safe (1, n)`. Returns a result tuple."
+	(x as :number) -> div/safe (1, x)
+}
+
 fn abs {
 	"Returns the absolute value of a number."
 	(0) -> 0
@@ -620,16 +637,13 @@ fn max {
 
 & additional list operations now that we have comparitors
 fn at {
-	"Returns the element at index n of a list or tuple. Zero-indexed: the first element is at index 0."
-	(xs as :list, n as :number) -> when {
-		neg? (n) -> nil
-		gte? (n, count (xs)) -> nil
-		true -> base :nth (n, xs)
-	}
-	(xs as :tuple, n as :number) -> when {
-		neg? (n) -> nil
-		gte? (n, count (xs)) -> nil
-		true -> base :nth (n, xs)
+	"Returns the element at index n of a list or tuple, or the byte at index n of a string. Zero-indexed: the first element is at index 0. Returns nil if nothing is found in a list or tuple; returns an empty string if nothing is found in a string."
+	(xs as :list, n as :number) -> base :nth (xs, n)
+	(xs as :tuple, n as :number) -> base :nth (n, xs)
+	(str as :string, n as :number) -> when {
+		neg? (n) -> ""
+		gte? (n, count (str)) -> ""
+		true -> base :slice (str, n, inc (n))
 	}
 	(_) -> nil
 }
@@ -741,21 +755,17 @@ fn update {
 }
 
 fn keys {
-	"Takes an associative collection and returns a list of keys in that collection. Returns an empty list on anything other than a collection."
-	(coll) -> if not (assoc? (coll))
-		then []
-		else do coll > list > map (first, _)
+	"Takes a dict and returns a list of keys in that dict."
+	(dict as :dict) -> do dict > list > map (first, _)
 }
 
 fn values {
-	"Takes an associative collection and returns a list of values in that collection. Returns an empty list on anything other than a collection."
-	(coll) -> if not (assoc? (coll))
-		then []
-		else do coll > list > map (second, _)
+	"Takes a dict and returns a list of values in that dict."
+	(dict) -> do dict > list > map (second, _)
 }
 
 fn diff {
-	"Takes two associate data structures and returns a dict describing their differences. Does this shallowly, offering diffs only for keys in the original dict."
+	"Takes two dicts and returns a dict describing their differences. Does this shallowly, offering diffs only for keys in the original dict."
 	(d1 as :dict, d2 as :dict) -> {
 		let key1 = keys (d1)
 		let key2 = keys (d2)
@@ -782,7 +792,7 @@ fn diff {
 }
 
 fn coll? {
-	"Returns true if a value is a collection: dict, struct, list, tuple, or set."
+	"Returns true if a value is a collection: dict, list, pkg, tuple, or set."
 	(coll as :dict) -> true
 	(coll as :list) -> true
 	(coll as :tuple) -> true
@@ -799,7 +809,7 @@ fn ordered? {
 }
 
 fn assoc? {
-	"Returns true if a value is an associative collection: a dict, struct, or namespace."
+	"Returns true if a value is an associative collection: a dict or a pkg."
 	(assoc as :dict) -> true
 	(assoc as :pkg) -> true
 	(_) -> false
@@ -807,10 +817,10 @@ fn assoc? {
 
 & TODO: consider merging `get` and `at`
 fn get {
-	"Takes a dict or struct, key, and optional default value; returns the value at key. If the value is not found, returns nil or the default value. Returns nil or default if the first argument is not a dict or struct."
+	"Takes a key, dict, and optional default value; returns the value at key. If the value is not found, returns nil or the default value."
 	(key as :keyword) -> get (key, _)
-	(key as :keyword, coll) -> base :get (key, coll)
-	(key as :keyword, coll, default) -> base :get (key, coll, default)
+	(key as :keyword, dict as :dict) -> get (key, dict)
+	(key as :keyword, dict as :dict, default) -> base :get (key, dict, default) 
 }
 
 & TODO: add sets to this?
@@ -1338,159 +1348,164 @@ fn penwidth {
 box state = nil
 
 pkg Prelude {
-	abs
-	add
-	and
-	angle
-	any?
-	append
-	assert!
-	assoc
-	assoc?
-	at
-	atan/2
-	back!
-	background!
-	between?
-	bg!
-	bgcolor
-	bk!
-	bool
-	bool?
-	box?
-	butlast
-	ceil
-	clear!
-	coll?
-	colors
-	concat
-	cos
-	count
-	dec
-	deg/rad
-	deg/turn
-	dict
-	dict?
-	diff
-	dissoc
-	dist
-	div
-	div/0
-	div/safe
-	doc!
-	downcase
-	each!
-	empty?
-	eq?
-	err
-	err?
-	even?
-	false?
-	fd!
-	filter
-	first
-	floor
-	fn?
-	fold
-	forward!
-	get
-	goto!
-	gt?
-	gte?
-	heading
-	heading/vector
-	home!
-	inc
-	inv
-	inv/0
-	join
-	keep
-	keys
-	keyword?
-	last
-	left!
-	list
-	load_turtle_state!
-	lt!
-	lt?
-	lte?
-	map
-	max
-	min
-	mod
-	mult
-	neg
-	neg?
-	neq?
-	nil?
-	not
-	odd?
-	ok
-	ok?
-	or
-	ordered?
-	p5_calls
-	pc!
-	pd!
-	pencolor
-	pencolor!
-	pendown!
-	pendown?
-	penup!
-	penwidth
-	penwidth!
-	pi
-	pos?
-	position
-	print!
-	prn!
-	pu!
-	pw!
-	rad/deg
-	rad/turn
-	random
-	random_int
-	range
-	render_turtle!
-	report!
-	reset_turtle!
-	rest
-	right!
-	round
-	rt!
-	second
-	set
-	set?
-	show
-	sin
-	slice
-	some
-	some?
-	split
-	square
-	state
-	store!
-	string
-	string?
-	sub
-	sum_of_squares
-	tan
-	tau
-	trim
-	tuple?
-	turn/deg
-	turn/rad
-	turtle_commands
-	turtle_state
-	turtle_states
-	type
-	unbox
-	unwrap!
-	unwrap_or
-	upcase
-	update
-	update!
-	values
-	words
-	zero?
+	abs & math
+	add & math
+	and & bool
+	angle & math
+	any? & dicts lists strings sets tuples
+	append & lists sets
+ 	assert! & errors
+	assoc & dicts
+	assoc? & dicts 
+	at & lists strings
+	atan/2 & math
+	back! & turtles
+	background! & turtles
+	between? & math
+	bg! & turtles
+	bgcolor & turtles
+	bk! & turtles
+	bool & bool
+	bool? & bool
+	box? & boxes
+	butlast & lists strings tuples
+	ceil & math
+	clear! & turtles
+	coll? & dicts lists sets tuples
+	colors & turtles
+	concat & string list set 
+	cos & math
+	count & string list set tuple dict
+	dec & math
+	deg/rad & math
+	deg/turn & math
+	dict & dict
+	dict? & dict
+	diff & dict
+	dissoc & dict
+	dist & math
+	div & math
+	div/0 & math
+	div/safe & math
+	doc! & env
+	downcase & string
+	each! & list 
+	empty? & list dict set string tuple
+	eq? & values
+	err & result
+	err? & result
+	even? & math
+	false? & bool
+	fd! & turtles
+	filter & list
+	first & list tuple
+	floor & math
+	fn? & functions
+	fold & lists
+	forward! & turtles
+	get & dicts
+	goto! & turtles
+	gt? & math
+	gte? & math
+	heading & turtles
+	heading/vector & math
+	home! & turtles
+	inc & math
+	inv & math
+	inv/0 & math
+	inv/safe & math
+	join & lists strings
+	keep & lists
+	keys & dicts
+	keyword? & keywords
+	last & lists tuples
+	left! & turtles
+	list & lists
+	list? & lists
+	load_turtle_state! & turtles
+	lt! & turtles
+	lt? & math
+	lte? & math
+	map & lists
+	max & math
+	min & math
+	mod & math
+	mult & math
+	neg & math
+	neg? & math
+	neq? & values
+	nil? & nil
+	not & bool
+	odd? & math
+	ok & results
+	ok? & results
+	or & bool
+	ordered? & lists tuples strings
+	p5_calls & turtles
+	pc! & turtles
+	pd! & turtles
+	pencolor & turtles
+	pencolor! & turtles
+	pendown! & turtles
+	pendown? & turtles
+	penup! & turtles
+	penwidth & turtles
+	penwidth! & turtles
+	pi & math
+	pos? & math
+	position & turtles
+	print! & environment
+	& prn! & environment
+	pu! & turtles
+	pw! & turtles
+	rad/deg & math
+	rad/turn & math
+	random & math dicts lists tuples sets
+	random_int & math
+	range & math lists
+	render_turtle! & turtles
+	report! & environment
+	reset_turtle! & turtles
+	rest & lists tuples
+	right! & turtles
+	round & math
+	rt! & turtles
+	second & lists tuples
+	sentence & lists strings
+	set & sets
+	set? & sets
+	show & strings
+	sin & math
+	slice & lists tuples strings
+	some & values
+	some? & values
+	split & strings
+	square & math
+	state & environment
+	store! & boxes
+	string & strings
+	string? & strings
+	strip & strings
+	sub & math
+	sum_of_squares & math 
+	tan & math
+	tau & math
+	trim & strings
+	tuple? & tuples
+	turn/deg & math
+	turn/rad & math
+	turtle_commands & turtles
+	turtle_state & turtles
+	turtle_states & turtles
+	type & values
+	unbox & boxes
+	unwrap! & results
+	unwrap_or & results
+	upcase & strings
+	update & dicts
+	update! & boxes
+	values & dicts
+	words & strings lists
+	ws? & strings
+	zero? & math
 }