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| author | Kaz Kylheku <kaz@kylheku.com> | 2017-07-15 10:22:53 -0700 |
|---|---|---|
| committer | Kaz Kylheku <kaz@kylheku.com> | 2017-07-15 10:22:53 -0700 |
| commit | d151853a6be4548c8a4d02b839b7dce689217a7d (patch) | |
| tree | 8fe2b02c2c3ecdc1a4df502b7884f1b22d16a205 /txr.1 | |
| parent | b15f6304249de5ba503bedc9944cb57aa1771cd8 (diff) | |
| download | txr-d151853a6be4548c8a4d02b839b7dce689217a7d.tar.gz txr-d151853a6be4548c8a4d02b839b7dce689217a7d.tar.bz2 txr-d151853a6be4548c8a4d02b839b7dce689217a7d.zip | |
carray: add offset to carray-buf.
* ffi.c (struct carray): New member, offs.
(make_carray): Initiialize offs member from new argument.
(copy_carray, carray_blank, carry_ptr, carray_sub,
carray_pun, carray_unum, carray_num): Pass zero offset to
(carray_buf): New optional parameter off_in.
(carray_buf_sync): Handle offset.
(ffi_init): Update registration of carray-buf.
* ffi.h (make_carray, carray_buf): Declaration updated.
* txr.1: Documented.
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 32 |
1 files changed, 28 insertions, 4 deletions
@@ -57707,7 +57707,7 @@ function, and of .coNP Function @ carray-buf .synb -.mets (carray-buf < buf << type ) +.mets (carray-buf < buf < type <> [ offset ]) .syne .desc The @@ -57718,15 +57718,39 @@ object which refers to the storage provided and managed by the buffer object .metn buf , providing a view of that storage, and manipulation thereof, as an array. +The optional +.meta offset +parameter specifies an offset from the start of the buffer to the +location which is interpreted as the start of the +.codn carray , +which extends from that offset to the end of the buffer. + +The default value is zero: the +.code carray +covers the entire buffer. + +If a value is specified, it must be in the range zero to the length of +.metn buf . + The .meta type argument must be a compiled FFI type whose size is nonzero. -The bytewise length of + +The +.code carray +is overlaid onto the storage of +.meta buf +as follows: + +First, +.meta offs +is subtracted from the bytewise length of .metn buf , as reported by .code length-buf -function , -is divided by the size of +function to produce the effective length of the storage to be used for the array. + +The effective length is divided by the size of .metn type , as reported by .codn ffi-size . |