X-Git-Url: https://pd.if.org/git/?p=lice;a=blobdiff_plain;f=lexer.h;fp=lexer.h;h=f0831fa68338b277c85a4317197222b7ae775a21;hp=0000000000000000000000000000000000000000;hb=d41dc131c73a91d200dbffab3a7786f6b2b51489;hpb=c9d92e71ffc96475abe19bd7dc7512df89b4f44d

diff --git a/lexer.h b/lexer.h
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+#ifndef LICE_LEXER_HDR
+#define LICE_LEXER_HDR
+/*
+ * File: lexer.h
+ *  Implements the interface for LICE's lexer
+ */
+#include <stdbool.h>
+
+/*
+ * Type: lexer_token_type_t
+ *  Type to describe a tokens type.
+ *
+ *  Remarks:
+ *   Implemented as a typedef of an enumeration, lexer_token_t
+ *   is used to describe the current lexer token. The following
+ *   tokens exist (as constants).
+ *
+ *  Tokens:
+ *    LEXER_TOKEN_IDENTIFIER        - Identifier
+ *    LEXER_TOKEN_PUNCT             - Language punctuation
+ *    LEXER_TOKEN_CHAR              - Character literal
+ *    LEXER_TOKEN_STRING            - String literal
+ *    LEXER_TOKEN_NUMBER            - Number (of any type)
+ *    LEXER_TOKEN_EQUAL             - Equal
+ *    LEXER_TOKEN_LEQUAL            - Lesser-or-equal
+ *    LEXER_TOKEN_GEQUAL            - Greater-or-equal
+ *    LEXER_TOKEN_NEQUAL            - Not-equal
+ *    LEXER_TOKEN_INCREMENT         - Pre/post increment
+ *    LEXER_TOKEN_DECREMENT         - Pre/post decrement
+ *    LEXER_TOKEN_ARROW             - Pointer arrow `->`
+ *    LEXER_TOKEN_LSHIFT            - Left shift
+ *    LEXER_TOKEN_RSHIFT            - Right shift
+ *    LEXER_TOKEN_COMPOUND_ADD      - Compound-assignment addition
+ *    LEXER_TOKEN_COMPOUND_SUB      - Compound-assignment subtraction
+ *    LEXER_TOKEN_COMPOUND_MUL      - Compound-assignment multiplication
+ *    LEXER_TOKEN_COMPOUND_DIV      - Compound-assignment division
+ *    LEXER_TOKEN_COMPOUND_MOD      - Compound-assignment moduluas
+ *    LEXER_TOKEN_COMPOUND_OR       - Compound-assignment bit-or
+ *    LEXER_TOKEN_COMPOUND_XOR      - Compound-assignment bit-xor
+ *    LEXER_TOKEN_COMPOUND_LSHIFT   - Compound-assignment left-shift
+ *    LEXER_TOKEN_COMPOUND_RSHIFT   - Compound-assignment right-shift
+ *    LEXER_TOKEN_AND               - Logical and
+ *    LEXER_TOKEN_OR                - Logical or
+ */
+typedef enum {
+    LEXER_TOKEN_IDENTIFIER,
+    LEXER_TOKEN_PUNCT,
+    LEXER_TOKEN_CHAR,
+    LEXER_TOKEN_STRING,
+    LEXER_TOKEN_NUMBER,
+    LEXER_TOKEN_EQUAL,
+    LEXER_TOKEN_LEQUAL,
+    LEXER_TOKEN_GEQUAL,
+    LEXER_TOKEN_NEQUAL,
+    LEXER_TOKEN_INCREMENT,
+    LEXER_TOKEN_DECREMENT,
+    LEXER_TOKEN_ARROW,
+    LEXER_TOKEN_LSHIFT,
+    LEXER_TOKEN_RSHIFT,
+    LEXER_TOKEN_COMPOUND_ADD,
+    LEXER_TOKEN_COMPOUND_SUB,
+    LEXER_TOKEN_COMPOUND_MUL,
+    LEXER_TOKEN_COMPOUND_DIV,
+    LEXER_TOKEN_COMPOUND_MOD,
+    LEXER_TOKEN_COMPOUND_AND,
+    LEXER_TOKEN_COMPOUND_OR,
+    LEXER_TOKEN_COMPOUND_XOR,
+    LEXER_TOKEN_COMPOUND_LSHIFT,
+    LEXER_TOKEN_COMPOUND_RSHIFT,
+    LEXER_TOKEN_AND,
+    LEXER_TOKEN_OR
+} lexer_token_type_t;
+
+/*
+ * Class: lexer_token_t
+ *  Describes a token in the token stream
+ */
+typedef struct {
+    /*
+     * Variable: type
+     *  The token type
+     */
+    lexer_token_type_t type;
+
+    union {
+        long  integer;
+        int   punct;
+        char *string;
+        char  character;
+    };
+} lexer_token_t;
+
+/*
+ * Function: lexer_islong
+ *  Checks for a given string if it's a long-integer-literal.
+ *
+ * Parameters:
+ *  string  - The string to check
+ *
+ * Remarks:
+ *  Returns `true` if the string is a long-literal,
+ *  `false` otherwise.
+ */
+bool lexer_islong(char *string);
+
+/*
+ * Function: lexer_isint
+ *  Checks for a given string if it's a int-integer-literal.
+ *
+ * Parameters:
+ *  string  - The string to check
+ *
+ * Remarks:
+ *  Returns `true` if the string is a int-literal,
+ * `false` otherwise.
+ */
+bool lexer_isint (char *string);
+
+/*
+ * Function: lexer_isfloat
+ *  Checks for a given string if it's a floating-point-literal.
+ *
+ * Parameters:
+ *  string  - The string to check
+ *
+ * Remarks:
+ *  Returns `true` if the string is floating-point-literal,
+ * `false` otherwise.
+ */
+bool lexer_isfloat(char *string);
+
+/*
+ * Function: lexer_ispunct
+ *  Checks if a given token is language punctuation and matches.
+ *
+ * Parameters:
+ *  token   - The token to test
+ *  c       - The punction to test if matches
+ *
+ * Remarks:
+ *  Returns `true` if the given token is language punctuation and
+ *  matches *c*.
+ */
+bool lexer_ispunct(lexer_token_t *token, int c);
+
+/*
+ * Function: lexer_unget
+ *  Undo the given token in the token stream.
+ *
+ * Parameters:
+ *  token   - The token to unget
+ */
+void lexer_unget(lexer_token_t *token);
+
+/*
+ * Function: lexer_next
+ *  Get the next token in the token stream.
+ *
+ * Returns:
+ *  The next token in the token stream or NULL
+ *  on failure or EOF.
+ */
+lexer_token_t *lexer_next(void);
+
+/*
+ * Function: lexer_peek
+ *  Look at the next token without advancing the stream.
+ *
+ * Returns:
+ *  The next token without advancing the token stream or NULL on failure
+ *  or EOF.
+ *
+ * Remarks:
+ *  The function will peek ahead to see the next token in the stream
+ *  without advancing the lexer state.
+ */
+lexer_token_t *lexer_peek(void);
+
+/*
+ * Function: lexer_token_string
+ *  Convert a token to a human-readable representation
+ *
+ * Parameters:
+ *  token   - The token to convert
+ *
+ * Returns:
+ *  A string representation of the token or NULL on failure.
+ */
+char *lexer_token_string(lexer_token_t *token);
+
+/*
+ * Function: lexer_marker
+ *  Get the line marker of where the lexer currently is.
+ *
+ * Remarks:
+ *  Currently returns file.c:line, will later be extended to also include
+ *  column marker. This is used in error reporting.
+ */
+char *lexer_marker(void);
+
+#endif