...while ((len = file.readBlock(buffer.ptr, buffer.sizeof)) != 0)
		context.update(buffer[0 .. len]);
	context...

...md5, this line can be found:
while ((len = fread(buffer, 1, buffer.sizeof, file)) != 0...

...len) dat.length=dat.length+32;
        dat[len]=t;
        len++;
    }
    void pushn(uint n) {
        len...

...that often conflict with local variables, like "len" or "src" or such. Unless the type...

...7000)
out = "const int primes[%d] = %s;" % (len(p), p)
print "\n".join(textwrap.wrap...

...where only _len is common
    void f(M)(M rhs) {
        _len = rhs._len;
        writefln("method...

...that bad, right?

   @property bool empty() { return _len == 0; }

   (we can use @prop if @property...

...len + entity.length)
+ dst.length / 2;

                           dst [index .. index + len] = t [0 .. len];
                           index += len...

...len + entity.length)
+ dst.length / 2;

                           dst [index .. index + len] = t [0 .. len];
                           index += len...

...now cached.
var len = things.length;
for ( int i = 0; i < len; i++ )
	stroke(things...