This section presents the interfaces required by every Modula-3 implementation. The versions included here have some minor changes and additions to the versions in [SPwM3] .
Text provides operations on text strings.
Thread provides synchronization primitives for multiple threads of control.
Word provides operations on unsigned words.
Real, LongReal, and ExtendedReal define the properties of the three floating-point types; for example, their bases and ranges.
RealFloat, LongRealFloat, and ExtendedFloat provide numerical operations related to the floating-point representation; for example, extracting the exponent of a number.
FloatMode provides operations for testing (and possibly setting) the behavior of the implementation in response to numeric conditions; for example, overflow.
This section also presents two related interfaces provided by SRC Modula-3 and recommended to other implementers, but not required:
Lex provides for parsing numbers and other data from an input stream.
Fmt provides for textual formatting of numbers and other data.