Access to the external environment: collection#1
Function to turn atomics into booleans for use in two-valued logics: boolean#1
Functions on numeric values: abs#1, ceilingabs#1, floorabs#1, roundabs#1, round-half-to-even#1
Formatting integers: format-integer#2, format-integer#3
Formatting numbers: format-numberreturn r#2, format-number#3
Trigonometric and exponential functions: pi#0, exp#1, exp10#1, log#1, log10#1, pow#2, sqrt#1, sin#1, cos#1, tan#1, asin#1, acos#1, atan#1, atan2#1
Functions to assemble and disassemble strings: codepoints-to-string#1, string-to-codepoints#1
Comparison of strings: compare#2, compare#3, codepoint-equal#2
Functions on string values: concat#2, string-join#1, string-join#2, substring#2, substring#3, string-length#0, string-length#1, normalize-space#0, normalize-space#1, normalize-unicode#1, normalize-unicode#2, upper-case#1, lower-case#1, translate#3
Functions based on substring matching: contains#2, contains#3, starts-with#2, starts-with#3, ends-with#2, ends-with#3, substring-before#2, substring-before#3, substring-after#2, substring-after#3
String functions that use regular expressions: matches#2, matches#3, replace#3, replace#4, tokenize#2, tokenize#3
Functions that manipulate URIs: resolve-uri#1, resolve-uri#2, encode-for-uri#1, iri-to-uri#1, escape-html-uri#1
General functions on sequences: empty#1, exists#1, head#1, tail#1, insert-before#3, remove#2, reverse#1, subsequence#2, subsequence#3, unordered#1
Function that compare values in sequences: distinct-values#1, distinct-values#2, index-of#2, index-of#3, deep-equal#2. deep-equal#3
Functions that test the cardinality of sequences: zero-or-one#1, one-or-more#1, exactly-one#1
Serializing functions: serialize#1 (unary)
Context information: current-dateTime#1, current-date#1, current-time#1, implicit-timezone#1, default-collation#1
Constructor functions: for all builtin types, with the name of the builtin type and unary. Equivalent to a cast expression.