Builtin function reference

GENERATED — do not edit by hand. Regenerate with python3 scripts/gen-builtin-docs.py after changing src/builtins.rs.

Palladium has 34 builtin functions. They are ordinary free functions: there is no prelude to import and no module path to qualify. They are defined in a single table (src/builtins.rs) that the type checker and the borrow checker both derive from, so a builtin cannot exist in one pass and not the other.

Their C implementations are emitted inline into every generated file; the file and path functions are thin wrappers over symbols supplied at link time by runtime/palladium_runtime.c.

Output

Writing to standard output, and aborting.

Signature	Notes
print(String)
print_int(i64)
panic(String)	borrows its string argument

String manipulation

Strings are immutable handles into an arena. string_char_at returns a char (N14-04), which is what the char_is_* predicates take; an index outside the string traps, because there is no char meaning 'no character'.

Signature	Notes
string_len(String) -> i64	borrows its string argument
string_concat(String, String) -> String	borrows its string argument
string_eq(String, String) -> bool	borrows its string argument
string_char_at(String, i64) -> char
string_substring(String, i64, i64) -> String
string_from_char(char) -> String
string_to_int(String) -> i64	borrows its string argument
int_to_string(i64) -> String

Character classification

Predicates over a char (N4-04).

Signature	Notes
char_is_digit(char) -> bool
char_is_alpha(char) -> bool
char_is_whitespace(char) -> bool
arg_count() -> i64
arg_at(i64) -> String

File I/O

The handle-based API. file_open returns an integer handle, or a negative value on failure.

Signature	Notes
file_open(String) -> i64	borrows its string argument
file_read_all(i64) -> String
file_read_line(i64) -> String
file_write(i64, String) -> bool
file_close(i64) -> bool
file_exists(String) -> bool	borrows its string argument

Enhanced I/O

Signature	Notes
path_exists(String) -> bool	borrows its string argument
path_is_file(String) -> bool	borrows its string argument
path_is_dir(String) -> bool	borrows its string argument
create_dir(String) -> i64	borrows its string argument
create_dir_all(String) -> i64	borrows its string argument
remove_file(String) -> i64	borrows its string argument
remove_dir(String) -> i64	borrows its string argument
remove_dir_all(String) -> i64	borrows its string argument
read_file_to_string(String) -> String	borrows its string argument
write_string_to_file(String, String) -> i64	borrows its string argument
file_flush(i64) -> i64
file_seek(i64, i64, i64) -> i64

Notes that bite

• string_char_at returns a char (N4-04/N14-04), not an i64. Use as i64 for the code point; an index outside the string traps rather than answering a sentinel.
• file_write returns bool, not a byte count.
• vec![x] is a macro that expands to a one-element array, not a growable vector.
• dbg!(x) expands to a call to print_debug, which is defined nowhere; it always fails.
• println! takes exactly one argument.

See the language specification for the full behaviour of each construct and the tutorial for worked examples.