lang • write

WRITE

WRITE [ # Stream , ] Expression AS Datatype WRITE [ # Stream , ] String [ , Length ] WRITE [ # Stream , ] Pointer , Length

Writing a specific datatype

The first syntax writes an expression to the stream Stream by using their binary representation.

If the stream is not specified, the standard output is used.

When writing a string, the length of the string is sent before the string contents.

See Binary Data Representation for more information.

The datatype of Expression can be one of the following : NULL, Boolean, Byte, Short, Integer, Long, Pointer, Single, Float, Date, String, Variant, any Array or Collection, or any structure.

If Expression is a collection, an array, or a structure, then its contents are written recursively.

When writing a structure, the structure type must be specified as Datatype.

If an unsupported datatype is written, or if a circular reference is detected, an error is raised.

This instruction uses the byte order of the stream to write the data.

Writing the contents of a string

The second syntax writes Length bytes from the string String to the specified stream.

If the stream is not specified, the standard output is used.

If Length is not specified, the length of String is used.

Writing the contents of memory

The third syntax writes Length bytes from the memory address Pointer to the specified stream.

If the stream is not specified, the standard output is used.

Length must be specified, otherwise nothing is done.

Compatibility with Gambas 2

BEWARE!

WRITE #Stream, Expression writes the binary form of Expression in Gambas 2.0. In Gambas 3.0 it writes Expression as a string.

So you HAVE to check all your WRITE instructions when converting a Gambas project from 2.0 to 3.0, and specify AS Datatype when need.

By default, the compiler supports the old READ syntax, and the old WRITE syntax too as it is compatible.

If you want to detect where you should rewrite your READ / WRITE syntax, you can compile your project by hand with the "--no-old-read-write-syntax" flag. Then the Length argument of WRITE becomes mandatory if the second syntax is used.

Using a Pointer as a stream is not possible anymore. Create a memory stream with the MEMORY instruction instead.

See also