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+# 34 — float text
+
+opcode 610 still prints six digits after the dot, and a tie in the next digit still rounds away from zero, so the existing float line does not move. it no longer gives up past about 1e32: the scaled magnitude is a base-2^32 integer, so a finite value prints its digits. `-0` stays `-0.000000`, and a nan is `nan` whatever its sign bit.
+
+opcode 618 (the word 1236) pops `(bits prec mode)`. mode 0 is the shortest spelling that parses back to the same bits: a plain decimal when the exponent is between -4 and 15, otherwise scientific (`1e+308`, `1e-10`, `-0`). mode 1 is fixed, `prec` digits after the dot. mode 2 is scientific, `prec` significant digits. `prec` is capped at 17. print and parse stay out of an o3 region, the same way 610 and 611 do.
+
+the parser keeps the digits of the word it is given (eighty, past that a sticky bit) and converts `significand * 10^exp` with the same integer arithmetic. ties round to even, which is why `9007199254740993` and `9007199254740992` are one double and the next integer is not. `inf`, `-inf`, `nan` and `-nan` are accepted, and an exponent past the double range is an infinity or a zero. nothing here calls libc, so the text does not depend on the host printf. the arm64 jit and llvm call the same C function the interpreter does; the arithmetic opcodes are still native.
+
+`tests/ftext.zc` prints `1e+308 1e-10 -0 inf -inf nan 0.1 1.50 1.250e+0 100000000000000000000.000000 1e+40 1111111111`. the ten ones are bit checks: `1.5` against `3/2`, `0.1` against `1/10`, the infinities, negative zero, the 17-digit tie, a subnormal, an underflow to zero, and a signed nan. the compiler and the runtime were not rebuilt for this; `fops.h` is the whole conversion.
+
+`test.sh` after this stage is 414 passed, 0 failed.