Standard Library

In addition to the AVM opcodes Tealish provides some builtin utility functions. All builtin Tealish functions are Capitalized to distinguish them from the AVM functions which are lowercase.

Cast(Expression, Type) → any

Tells the compiler to treat the expression as the given type. The compiler adds a runtime type length assertion.

bytes[32] address = Cast(Txn.ApplicationArgs[0], bytes[32])

UncheckedCast(Expression, Type) → any

Tells the compiler to treat the expression as the given type. The compiler does not add any runtime type length assertion.

bytes[32] address = UncheckedCast(Txn.ApplicationArgs[0], bytes[32])

Concat(bytes, bytes, ...) → bytes

Concatenates multiple byte strings together.

bytes foo = Concat(a, b, c, d)

Rpad(bytes, len) → bytes

Pads the byte string with 0 bytes (”\x00”) to the right.

bytes[10] b = Rpad("abc", 10)
assert(b == "abc\x00\x00\x00\x00\x00\x00\x00")

Lpad(bytes, len) → bytes

Pads the byte string with 0 bytes (”\x00”) to the left.

bytes[10] b = Lpad("abc", 10)
assert(b == "\x00\x00\x00\x00\x00\x00\x00abc")

SizeOf(Struct) → int

Returns the size of a struct type as a compile time constant.

Item item1 = bzero(SizeOf(Item))

Address(address) → bytes

Supports hardcoding of address constants in contracts in the standard Algorand base32 format. Note: the address must be a constant at compile time.

const TINYMAN = Address("RIKLQ5HEVXAOAWYSW2LGQFYGWVO4J6LIAQQ72ZRULHZ4KS5NRPCCKYPCUU")

ARC28Event(signature, bytes, ...) → bytes

Generates an ARC28 compliant byte string for logging event messages. The message is prefixed with the first 4 bytes of the SHA512_256 hash of the signature.

log(ARC28Event("set_manager(address)", new_manager))

# The above line generates the following Teal:
pushbytes 0xba87e7f4                                    // SHA512_256("set_manager(address)")[:4]
load 4                                                  // new_manager
concat
log