# Copyright (C) 2011, Parrot Foundation. =head1 NAME docs/deprecations/deprecations_3_0.pod - Parrot Deprecations for 3.0 =head1 Parrot Deprecations for 3.0 =head2 PARROT_ERRORS_GLOBALS_FLAG =head3 Description The PARROT_ERRORS_GLOBALS_FLAG constant has been removed. =head3 Rational This flag does not modify the behaviour of parrot in any way. =head3 Replacment Remove all code attempting to set/unset this flag. It didn't do anything anyways. =head2 CodeString =head3 Description The CodeString PMC has been removed =head3 Rational Equivalent and more efficient functionality is available from StringBuilder. =head3 Replacment CodeString contains a number of convenience methods in addition to its core functionality. It is easier to replace these first. =over 4 =item * CodeString.lineof can be replaced by PGE;Util;line_number =item * CodeString.unique can be replaced by PGE;Util;unique, PAST;Compiler;unique, or PAST;Compiler;uniquereg =item * CodeString.escape can be replaced by PGE;Util;pir_str_escape =item * CodeString.key can be replaced by PGE;Util;pir_key_escape =item * CodeString.charname_to_ord can be replaced by the find_codepoint opcode =back After these replacements, StringBuilder can be substituted for CodeString by changing .emit to .append_format. append_format does not add newlines, so these must be added to the format string. =head2 :unique_reg PIR value flag =head3 Description The :unique_reg flag on registers in PIR is no longer available. =head3 Rational It doesn't do anything. Also, this is a terrible way to work around register allocator failures if/when we get a register allocator. =head3 Replacment s/:unique_reg//g =head2 .nci_call and .meth_call PIR special forms Specifying the type of call being performed is no longer required thanks to the magic of virtual dispatch. =head3 Rational They're old, crufty, and don't do anything that cannot be acheived by .call. Except obfuscasion of course. =head3 Replacment Use .call. It should be a simple text replacement fix. =head2 Indirect Register Access Ops =head3 Description Opcodes that access registers that are not their direct arguments are deprecated. Note, however, that direct arguments does include keys and pcc ops. Ops that are known to have this behaviour are clear{i,n,s,p} and set{i,n,s,p}_ind. These have been removed. No other core ops are known to have this behaviour. If you've created a dynop that has this behaviour, it and code using it is subject to breakage without notice (we reserve the right to implement optimizers). =head3 Rational They don't fit well with the level of the rest of parrot's opcodes. They make register lifetime analysis impossible, preventing many optimizations. =head3 Replacment If you really are using this, rethink your code. Stop using the register frame as an aggregate. Use an object aggregate in stead. =head2 Exchange Op =head3 Description The exchange ops are deprecated. =head3 Rational They operate at too low a level to be useful as parrot ops. =head3 Replacment You aren't using this. Seriously? .macro xchg_int(a, b) $I0 = .a .a = .b .b = $I0 .endm =head2 PIR string literals with charset and encoding are deprecated =head3 Description PIR string literals of the form encoding:charset:"string" are deprecated. =head3 Rational After the charset/encoding merge, they're unneeded. =head3 Replacment They can be replaced with encoding:"string" The encoding should be one of the new unified encodings. =head2 Remaining string_* functions are deprecated =head3 Description The string_* functions have been deprecated for a while. The remaining functions are: string_make string_ord string_chr string_to_cstring_nullable string_max_bytes string_increment =head3 Rational They're old cruft. =head3 Replacment string_make should be replaced with Parrot_str_new_init. You can use Parrot_find_encoding to get an encoding from a cstring. Replace string_ord with Parrot_str_indexed. Replace string_chr with Parrot_str_chr. Replace string_to_cstring_nullable with Parrot_str_to_cstring. string_max_bytes and string_increment will be removed. =head2 Method lower in String PMC =head3 Description The method lower in the String PMC has been removed. =head3 Rational HLLs may need its own version with different name and semantic, having a generic one is confusing. For other usages string registers are more convenient. =head3 Replacment Use string registers and the downcase opcode. For HLLs, provide its own version in the HLL mapped String type. =cut