From 7ba99e9715c1fa3cd00fe6d9ac74b9a15eeac706 Mon Sep 17 00:00:00 2001 From: Andrew Kelley Date: Sat, 26 Dec 2015 15:43:40 -0700 Subject: [PATCH] analyze if maybe var expressions --- example/guess_number/main.zig | 2 +- src/analyze.cpp | 76 +++++++++++++++++++++++++---------- src/analyze.hpp | 6 +++ 3 files changed, 61 insertions(+), 23 deletions(-) diff --git a/example/guess_number/main.zig b/example/guess_number/main.zig index fffb9e6f8..cbef1fb7d 100644 --- a/example/guess_number/main.zig +++ b/example/guess_number/main.zig @@ -12,7 +12,7 @@ fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 { const answer = rand_int(&rand_state, 0, 100) + 1; while true { - line = readline("\nGuess a number between 1 and 100: "); + const line = readline("\nGuess a number between 1 and 100: "); if const guess ?= parse_number(line) { if (guess > answer) { diff --git a/src/analyze.cpp b/src/analyze.cpp index 27db0ce40..2be84ffa5 100644 --- a/src/analyze.cpp +++ b/src/analyze.cpp @@ -661,6 +661,8 @@ static bool num_lit_fits_in_other_type(CodeGen *g, TypeTableEntry *literal_type, } else { return false; } + case TypeTableEntryIdMaybe: + return num_lit_fits_in_other_type(g, literal_type, other_type->data.maybe.child_type); } zig_unreachable(); } @@ -1220,11 +1222,11 @@ static TypeTableEntry *analyze_bin_op_expr(CodeGen *g, ImportTableEntry *import, zig_unreachable(); } -static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableEntry *import, - BlockContext *context, TypeTableEntry *expected_type, AstNode *node) +static VariableTableEntry *analyze_variable_declaration_raw(CodeGen *g, ImportTableEntry *import, + BlockContext *context, AstNode *source_node, + AstNodeVariableDeclaration *variable_declaration, + bool expr_is_maybe) { - AstNodeVariableDeclaration *variable_declaration = &node->data.variable_declaration; - TypeTableEntry *explicit_type = nullptr; if (variable_declaration->type != nullptr) { explicit_type = resolve_type(g, variable_declaration->type); @@ -1238,19 +1240,28 @@ static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableE TypeTableEntry *implicit_type = nullptr; if (variable_declaration->expr != nullptr) { implicit_type = analyze_expression(g, import, context, explicit_type, variable_declaration->expr); - if (implicit_type->id == TypeTableEntryIdUnreachable) { - add_node_error(g, node, + if (implicit_type->id == TypeTableEntryIdInvalid) { + // ignore the poison value + } else if (expr_is_maybe) { + if (implicit_type->id == TypeTableEntryIdMaybe) { + implicit_type = implicit_type->data.maybe.child_type; + } else { + add_node_error(g, source_node, buf_sprintf("expected maybe type")); + implicit_type = g->builtin_types.entry_invalid; + } + } else if (implicit_type->id == TypeTableEntryIdUnreachable) { + add_node_error(g, source_node, buf_sprintf("variable initialization is unreachable")); implicit_type = g->builtin_types.entry_invalid; } else if (implicit_type->id == TypeTableEntryIdNumberLiteral) { - add_node_error(g, node, + add_node_error(g, source_node, buf_sprintf("unable to infer variable type")); implicit_type = g->builtin_types.entry_invalid; } } if (implicit_type == nullptr && variable_declaration->is_const) { - add_node_error(g, node, buf_sprintf("variables must have initial values or be declared 'mut'.")); + add_node_error(g, source_node, buf_sprintf("variables must have initial values or be declared 'mut'.")); implicit_type = g->builtin_types.entry_invalid; } @@ -1259,7 +1270,7 @@ static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableE VariableTableEntry *existing_variable = find_local_variable(context, &variable_declaration->symbol); if (existing_variable) { - add_node_error(g, node, + add_node_error(g, source_node, buf_sprintf("redeclaration of variable '%s'", buf_ptr(&variable_declaration->symbol))); } else { VariableTableEntry *variable_entry = allocate(1); @@ -1267,13 +1278,20 @@ static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableE variable_entry->type = type; variable_entry->is_const = variable_declaration->is_const; variable_entry->is_ptr = true; - variable_entry->decl_node = node; + variable_entry->decl_node = source_node; context->variable_table.put(&variable_entry->name, variable_entry); return variable_entry; } return nullptr; } +static VariableTableEntry *analyze_variable_declaration(CodeGen *g, ImportTableEntry *import, + BlockContext *context, TypeTableEntry *expected_type, AstNode *node) +{ + AstNodeVariableDeclaration *variable_declaration = &node->data.variable_declaration; + return analyze_variable_declaration_raw(g, import, context, node, variable_declaration, false); +} + static TypeTableEntry *analyze_number_literal_expr(CodeGen *g, ImportTableEntry *import, BlockContext *block_context, TypeTableEntry *expected_type, AstNode *node) { @@ -1397,37 +1415,51 @@ static TypeTableEntry *analyze_continue_expr(CodeGen *g, ImportTableEntry *impor return g->builtin_types.entry_unreachable; } -static TypeTableEntry *analyze_if_bool_expr(CodeGen *g, ImportTableEntry *import, BlockContext *context, - TypeTableEntry *expected_type, AstNode *node) +static TypeTableEntry *analyze_if_then_else(CodeGen *g, ImportTableEntry *import, BlockContext *context, + TypeTableEntry *expected_type, AstNode *then_block, AstNode *else_node, AstNode *parent_node) { - analyze_expression(g, import, context, g->builtin_types.entry_bool, node->data.if_bool_expr.condition); - - TypeTableEntry *then_type = analyze_expression(g, import, context, expected_type, - node->data.if_bool_expr.then_block); + TypeTableEntry *then_type = analyze_expression(g, import, context, expected_type, then_block); TypeTableEntry *else_type; - if (node->data.if_bool_expr.else_node) { - else_type = analyze_expression(g, import, context, expected_type, node->data.if_bool_expr.else_node); + if (else_node) { + else_type = analyze_expression(g, import, context, expected_type, else_node); } else { else_type = g->builtin_types.entry_void; - else_type = resolve_type_compatibility(g, context, node, expected_type, else_type); + else_type = resolve_type_compatibility(g, context, parent_node, expected_type, else_type); } if (expected_type) { return (then_type->id == TypeTableEntryIdUnreachable) ? else_type : then_type; } else { - return resolve_peer_type_compatibility(g, context, node, - node->data.if_bool_expr.then_block, node->data.if_bool_expr.else_node, + return resolve_peer_type_compatibility(g, context, parent_node, + then_block, else_node, then_type, else_type); } } +static TypeTableEntry *analyze_if_bool_expr(CodeGen *g, ImportTableEntry *import, BlockContext *context, + TypeTableEntry *expected_type, AstNode *node) +{ + analyze_expression(g, import, context, g->builtin_types.entry_bool, node->data.if_bool_expr.condition); + + return analyze_if_then_else(g, import, context, expected_type, + node->data.if_bool_expr.then_block, + node->data.if_bool_expr.else_node, + node); +} + static TypeTableEntry *analyze_if_var_expr(CodeGen *g, ImportTableEntry *import, BlockContext *context, TypeTableEntry *expected_type, AstNode *node) { assert(node->type == NodeTypeIfVarExpr); - zig_panic("TODO analyze_if_var_expr"); + + BlockContext *child_context = new_block_context(node, context); + + analyze_variable_declaration_raw(g, import, child_context, node, &node->data.if_var_expr.var_decl, true); + + return analyze_if_then_else(g, import, child_context, expected_type, + node->data.if_var_expr.then_block, node->data.if_var_expr.else_node, node); } static TypeTableEntry * analyze_expression(CodeGen *g, ImportTableEntry *import, BlockContext *context, diff --git a/src/analyze.hpp b/src/analyze.hpp index 81180402c..b53e7849a 100644 --- a/src/analyze.hpp +++ b/src/analyze.hpp @@ -55,6 +55,10 @@ struct TypeTableEntryNumLit { NumLit kind; }; +struct TypeTableEntryMaybe { + TypeTableEntry *child_type; +}; + enum TypeTableEntryId { TypeTableEntryIdInvalid, TypeTableEntryIdVoid, @@ -66,6 +70,7 @@ enum TypeTableEntryId { TypeTableEntryIdArray, TypeTableEntryIdStruct, TypeTableEntryIdNumberLiteral, + TypeTableEntryIdMaybe, }; struct TypeTableEntry { @@ -84,6 +89,7 @@ struct TypeTableEntry { TypeTableEntryArray array; TypeTableEntryStruct structure; TypeTableEntryNumLit num_lit; + TypeTableEntryMaybe maybe; } data; // use these fields to make sure we don't duplicate type table entries for the same type